Updates and Corrections—October 2023

To accompany the eBird/Clements Checklist v2023 spreadsheet

Species Gains and Losses

Splits

Chirruping Nightjar Caprimulgus griseatus is split from Savanna Nightjar Caprimulgus affinis (Clements 2007:183)

Summary: The Philippines gains another endemic species, the vocally distinct Chirruping Nightjar, split from the widespread Asian Savannah Nightjar.

Details: Numerous earlier authors have considered the monticolus group of the Asian continent and Taiwan to be a distinct species from the insular affinis group based on its browner plumage and larger size (e.g., Sharpe 1901, Rothschild 1927, Peters 1940, Howard and Moore 1991). However, the monticolus and affinis groups have been united by most authors (summarized in Sangster et al. 2021a; also Marshall 1978), and four taxa treated as conspecific with affinis were initially described as full species, including C. griseatus of the Philippines. A recent analysis of vocalizations showed that the Savannah Nightjar C. affinis is comprised of three vocal groups that are distinguishable on statistical analyses (Sangster et al. 2021a), and considered this to indicate that three species are involved. However, to the human ear, songs of affinis and monticolus can hardly be distinguished and they are very similar on sonograms, though differing consistently in details, and experiments demonstrating reciprocal differences in response to playback have not been published. However, the songs of griseatus of the northern Philippines differ much more markedly in structure from both the affinis and monticolus groups on sonagrams, and they have a much clearer tone than either of the above. This led to the conclusion by WGAC (followed by Clements et al. 2023 and Gill et al. 2023, IOC v.13.2) that griseatus should be treated as specifically distinct, but that monticolus should continue to be treated as conspecific with affinis unless it can be demonstrated that the seemingly minor differences in vocal structure (to human ears) would actually function as an isolating mechanism, and/or the demonstration of deep genetic divergence indicative of long isolation. The Mindanao subspecies mindanensis is extremely poorly known and only provisionally included with griseatus. Given that C. griseatus, as with C. affinis, is a bird of open areas such as dry fields and cities, its conservation status is unlikely to be of concern in the near future.

English names: There is no familiar, suitable English name for C. griseatus, so the name “Chirruping” Nightjar was chosen to reflect the species’ voice, its most characteristic distinguishing feature.

Tibetan Sand-Plover Anarhynchus atrifrons is split from Lesser (now Siberian) Sand-Plover A. mongolus (Clements 2007:94–95)

Summary: The Lesser Sand-Plover populations that breed in two widely separate parts of Asia are not each others’ closest relatives, and are split as Tibetan and Siberian Sand-Plover. While they can be identified in breeding plumage, their identification from each other and the Greater Sand-Plover in non-breeding areas will be a major challenge.

Details:The sand-plovers (Anarhynchus, formerly in Charadrius; see Generic changes section for details) have long been recognized to form three main groups that essentially replace each other geographically and that are field-identifiable in breeding plumage at least. All three were originally described as distinct species, and Peters (1934) did not list the two forms he united in C. mongolus contiguously with C. leschenaultii. Only the Greater Sand-Plover A. leschenaultii, which occupies a geographically intervening desertic breeding area between the montane steppe areas in which the north-east Asian mongolus group and the central Asian atrifrons groups breed, has generally been considered a full species. Nevertheless, suggestions that A. mongolus includes two species have been frequent (e.g., Hirschfeld et al. 2000), and Livezey (2010) and Eaton et al. (2016) recently treated all three as full species.

Wei et al. (2022a) showed that, in both mtDNA and genome-wide phylogenies and with good support, the leschenaultii and mongolus groups are sister taxa, with the atrifrons group being sister to that clade. They also carried out a vocal analysis which showed that the mongolus group is more vocally divergent from the leschenaultii and atrifrons groups than either of the latter two are from each other. Thus, WGAC (followed by Clements et al. 2023 and Gill et al. 2023, IOC v.13.2) considers that the traditional two-species treatment is clearly unwarranted, and a single-species treatment is considered unjustified based on the vocal differences and apparent breeding parapatry or narrow sympatry of the leschenaultii and atrifrons groups.

Field identification of non-breeding sand-plovers has always been challenging, and will now require a three-way instead of two-way separation. While many individuals will have to remain indeterminate, some can be reliably identified (e.g., Hirschfeld et al. 2000, Eaton et al. 2016).

English names: The English names adopted here are those that have been widely used in the above sources.

Australian Tern Gelochelidon macrotarsa is split from Gull-billed Tern Gelochelidon nilotica (Clements 2007:104–105)

Summary:Australia now has a breeding endemic tern species with the split of the Australian Tern, which differs from the widespread Gull-billed Tern in numerous often subtle ways. Non-breeders of the two overlap at least from eastern Indonesia to northwestern Australia, though they are often identifiable given adequate views or photos.

Details: Saunders (1876) lumped the Australian breeding form of Gelochelidon into G. nilotica with the words “I can see no ground for considering Mr. Gould’s Sterna macrotarsa from Australia to be specifically distinct”, and although this statement lacks any indication of material examined or other compelling rationale, Saunders’s decision has long been generally (but not universally, see e.g., North 1913–1914) followed. More recently, differences between macrotarsa and the other forms of nilotica (which are much more homogeneous) in structure, plumages, molt, behavior, and ecology (including nomadism, unpredictable breeding, and piracy in macrotarsa, unlike nilotica) were elucidated (Mees 1982, Rogers et al. 2005). Tavares and Baker (2008) found two distinct COI clusters evidently comprising small-billed G. nilotica affinis and large-billed macrotarsa, respectively, that they considered might represent unrecognized species-level entities. del Hoyo and Collar (2014) considered that macrotarsa met their criteria for species status, and were followed in this treatment by Gill and Donsker (2019; IOC v.9.2) and the Working List of Australian Birds v4 (https://birdata.birdlife.org.au/whats-in-a-name). While little genetic evidence appears to be yet available, and possible vocal differences are inadequately documented, the bulk of evidence is considered by WGAC and Clements et al. (2023) to better align with species status for macrotarsa.

English names: The English name Australian Gull-billed Tern for G. macrotarsa, used by del Hoyo and Collar (2014) and subsequent HBW and BirdLife Checklists, and the Working List of Australian Birds, necessitates modification of the name Gull-billed Tern for G. nilotica, for which these authors use Common Gull-billed Tern. Gill and Donsker (2019, IOC v.9.2) elected instead to use Australian Tern for G. macrotarsa and Gull-billed Tern for G. nilotica, and the Clements/eBird checklist now follows suit, as the name for the widespread and familiar (but not usually common) nilotica requires no change, and macrotarsa is the only full species of tern that is a breeding endemic to Australia.

Northern Royal Albatross Diomedea sanfordi is split from Southern Royal (formerly Royal) Albatross Diomedea epomophora (Clements 2007:9)

Summary: The newly split Northern Royal Albatross of South and Chatham islands can usually be distinguished at sea from the more numerous Southern Royal from Auckland and Campbell islands, if views are sufficiently good and photos show the leading edge of the wing.

Details: The Northern Royal Albatross D. sanfordi was originally named as a full species (Murphy 1917), but it is very closely related to the Southern Royal Albatross D. epomophora (Chambers et al. 2009). Nevertheless, it is fairly readily distinguished on plumage at all ages, and also is generally smaller. Northern and Southern Royals occupy largely separate breeding ranges in the New Zealand region, though there are a few records of mixed pairs at Taiaroa Head, South Island and Enderby Island, Auckland Islands (Taylor 2000). Despite their close approach and some level of gene flow, they have however maintained a greater degree of phenotypic difference than that found within any other species of albatross. Levels of genetic divergence between albatross species are typically low, and rarely, hybridization occurs even between other unequivocally specifically distinct albatross species (Phillips et al. 2018, Jones et al. 2020).

Although long treated as conspecific, the ACAP (Agreement on the Conservation of Albatrosses and Petrels, https://www.acap.aq/documents/working-groups/taxonomy-working-group/taxonomy-wg-reports/195-3rd-report-of-taxonomy-wg-2007/file) considers them separate species, as do numerous authorities (e.g., Gill and Donsker 2009, IOC v.2.1, del Hoyo and Collar 2014), and several field guides. While their specific status will remain a matter of opinion, WGAC and the Clements/eBird checklist (Clements et al. 2023) have now adopted the split.

English names: Northern Royal and Southern Royal are both appropriate names that have achieved a high level of familiarity.

Antipodean Albatross Diomedea antipodensis, Amsterdam Albatross D. amsterdamensis, and Tristan Albatross D. dabbenena are split from Wandering (now Snowy) Albatross D. exulans (Clements 2007:9)

Summary: The four-way split of the Wandering Albatross complex means all great albatross sightings should be thoroughly photo-documented whenever possible. Much remains to be learned of their at-sea distributions, and Snowy can occur in any southern waters, but in the south Atlantic, Tristan is the other most likely species; in the south Pacific, Antipodean; and Amsterdam is rare in the south-central Indian Ocean.

Details: Species limits of the Wandering Albatross complex have long been contentious, and until recently two species were generally recognized, the widespread Wandering Albatross D. exulans and the Amsterdam Albatross D. amsterdamensis, only described in 1983, and then lumped into D. exulans in Clements (2005). Several authorities, however, including Gill and Donsker (2009, IOC v.2.1) have long recognized four species in the complex.

The lower-latitude breeding populations of Wandering-complex albatrosses from the Tristan group (mainly Gough Island) and Antipodes region have each been shown to be genetically distinct (e.g., Alderman et al. 2005), and the Amsterdam Island population is now known to have unique haplotypes and extremely low genetic diversity likely related to the bottleneck effect (Rains et al. 2011). In contrast, there is extremely low population structuring across the wide subantarctic breeding range of D. exulans sensu stricto (Burg and Croxall 2004, Rheindt and Austin 2005, Milot et al. 2007, 2008), showing panmixia despite the great distances between many breeding islands. Clearly, despite its extreme vagility, exulans rarely if ever interbreeds with any of the more northerly breeding taxa, which are not each other’s closest relatives, and hence a four-species approach in the Wandering Albatross complex is adopted by WGAC and the Clements Checklist.

English names: Because the name Wandering Albatross has long been used to refer to all these taxa, the Clements/eBird checklist has adopted the name Snowy Albatross for Diomedea exulans sensu stricto. This name is appropriate given that adult males are the whitest of all albatrosses, and it has already become entrenched and familiar. The other three taxa have apt and widely adopted geographic names, all adopted by the Clements/eBird checklist.

Indian Yellow-nosed Albatross Thalassarche carteri is split from Atlantic Yellow-nosed (formerly Yellow-nosed) Albatross T. chlororhynchos (Clements 2007:9)

Summary: The split of Indian Yellow-nosed Albatross mainly of the southern Indian Ocean from Atlantic Yellow-nosed Albatross (mainly of the southern Atlantic) seems unlikely to cause much confusion in field identification except in southern African waters, but observers should always document any sightings photographically as much as possible.

Details: The Yellow-nosed Albatross T. chlororhynchos is comprised of two widely allopatric breeding populations, the nominate on Gough and Tristan da Cunha in the south Atlantic and carteri on several islands in the south Indian Ocean. These have been considered separated species by several authors (e.g., Gill and Donsker 2009, IOC v.2.1). However, at-sea distributions of breeding birds from Gough (chlororhynchos) and Prince Edward Island (carteri) approach closely (Makhado et al. 2018), and non-breeders overlap in southern African waters. These two forms, while broadly similar, differ consistently in several aspects of culmen shape and size as well as in head coloration in most plumages (Flood 2015). In a study of samples from breeding islands as well as bycatch (Abeyrama et al. 2021), the great majority of samples were correctly identified, which was considered by WGAC to support species status for carteri.

English names: Since species status for carteri was advocated for by Robertson and Nunn (1998), they have been treated thus by several authorities, and, while recognizing that this treatment will likely continue to be controversial, WGAC and the Clements/eBird checklist now follow suit. The English names are appropriate and have achieved a degree of stability such that change seems unwarranted.

Jamaican Petrel Pterodroma caribbaea is split from Black-capped Petrel Pterodroma hasitata (Clements 2007:10)

Summary: The little-known all-dark Jamaican Petrel, now treated as a full species, is probably extinct, but as its breeding area is difficult to access and it could be confused with other species at sea, it might yet be rediscovered.

Details: The Black-capped Petrel Pterodroma hasitata of the Caribbean and Gulf Stream was long thought to include both dark-faced and light-faced morphs, as well as (by some authorities) the all-dark Jamaican Petrel P. [h.] caribbaea. Murphy (1936) stated “I consider it highly probable that this bird and the Black-capped were color phases of the same species.” However, a strong rationale for the lump of caribbaea into hasitata was never published, and Imber (pers. comm. in Simons et al. 2013) opined that caribbaea may be most closely related to the P. feae superspecies.

All the above forms were thought to be extinct for a considerable time, but while the dark- and light-faced morphs have been rediscovered and are now much better known, the Jamaican Petrel has not, despite searches of its known breeding areas (as detailed in Simons et al. 2013) and despite much greater recent pelagic coverage.

Recent reviews of the evidence, which includes its all-dark plumage (not attributable to a “color phase”, as it occurs only in this plumage), different size and leg coloration, and a putatively distinct feather louse community, have led some authorities (e.g., Brooke 2004, Gill and Donsker 2012, IOC v.3.1, del Hoyo and Collar 2014) to consider caribbaea a separate species, and as there is no evidence to the contrary, WGAC and Clements et al. (2023) now follow the treatment of the apparently extinct Jamaican Petrel P. caribbaea as specifically distinct. The issue is currently being considered by NACC.

English names: The well-established English names Jamaican Petrel and Black-capped Petrel are apt and unlikely to cause much confusion, so no change is required.

Eastern Cattle Egret Bubulcus coromandus is split from Western Cattle (formerly Cattle) Egret B. ibis (Clements 2007:20)

Summary: The Eastern Cattle Egret of Asia and Australasia looks very different in breeding plumage from Western Cattle Egret of Europe, Asia, and the Western Hemisphere, but when not breeding, proportional differences are key to their identification.

Details: The numerous striking differences in breeding plumage and in structure between the two universally recognized forms of Cattle Egret Bubulcus ibis have long led to discussion of their possible specific distinctness (e.g., Payne and Risley 1976). Rasmussen and Anderton (2005) recognized them as specifically distinct based on morphology as well as differences observed in some vocalization types (which have been questioned and require formal analysis), and Gill and Wright (2008, IOC v.1.6) treated them as two species. Ahmed (2011) presented detailed information on morphological differences. The several structural differences between ibis and coromandus, which are usually obvious even in life and can lead to confusion of coromandus with Medium Egret Ardea intermedia, are non-clinal in nature despite the close approach of both forms in western Asia. However, populations on the Seychelles and Chagos, Indian Ocean have been considered subspecies seychellarum or a synonym of ibis but are likely the result of some hybridization where coromandus have immigrated into the small-island range of ibis (e.g., Carr 2015). Despite the apparent limited (but not well-documented) hybridization in these insular situations, WGAC and Clements et al. (2023) consider that the bulk of evidence supports species status, and this is adopted herein.

English names: The English names Western Cattle Egret and Eastern Cattle Egret are now widely adopted and familiar, hence their continued usage here.

Yellow-billed Egret Ardea brachyrhyncha and Plumed Egret A. plumifera are split from Medium (formerly Intermediate) Egret A. intermedia (Clements 2007:20)

Summary: The mid-sized white egrets distributed in Africa, Asia, and Australia are readily identified on their breeding grounds and are now recognized as different species. Their non-breeding ranges are not entirely known and vagrant individuals may pose identification challenges.

Details: For most of the year, when in non-breeding plumage, the mid-sized white egrets of Asia through Africa strongly resemble each other, especially as specimens, to the point that Mees (1975, 1982) merged all three into a single taxon. However, it is now known that during the brief period when in high breeding color, the nominate form with its intervening Asian range shows very different colors from the African brachyrhyncha and Australian plumifera, which are similar in these characteristics though they are very broadly allopatric from each other and show differences in proportions. None of the taxa involved are highly vocal, and confidently identified recordings of known homology are few, but some putative differences in display and vocalizations have been noted (del Hoyo and Collar 2014). The pronounced differences in breeding coloration between intermedia and the other taxa, which differ in other ways, is considered to be more consistent with treatment as separate species than as a single highly polytypic species (Rasmussen and Anderton 2012), del Hoyo and Collar (2014), and now WGAC and Clements et al. (2023) align on this three-species treatment.

English names: To minimize confusion, the English name Intermediate Egret is now retired, and we adopt Medium Egret for the Asian species, which occurs widely alongside Little and Great Egrets. African brachyrhyncha has long been also known as Yellow-billed Egret, while the name Plumed Egret has achieved familiarity for Australian plumifera (which typically has longer breeding plumes than the other taxa), so these names are adopted here.

American Goshawk Accipiter atricapillus is split from Northern (now Eurasian) Goshawk A. gentilis (Clements 2007:43)

Brief summary: North America now has its own species of goshawk, adults of which differ in several ways from its Eurasian relative. Identification will not be impacted except by the possibility of an extremely rare vagrant.

Details: Although long treated as separate species, Hartert (1914) ranked atricapillus as a subspecies of A. gentilis with the phrase (roughly translated as) “Represents our goshawk in North America”, a treatment that has endured until the present. However, molecular analyses suggest that atricapillus and gentilis may not be sister taxa (e.g., Kunz et al. 2019), and they have been shown to differ in certain vocalizations, as well as adult plumage and iris color (Sangster 2022). Thus, continuing to treat A. gentilis as Holarctic in distribution appears untenable, and Clements et al. (2023) and Gill et al. (2023, IOC v.13.2) now follow NACC (Chesser et al. 2023) and the WGAC consensus in treating A. atricapillus as an independent species.

English names: The English name American Goshawk was in use prior to its lumping into A. gentilis, and we consider it appropriate. The name Northern Goshawk has a long history of use for both daughter species, so Clements et al. (2023) follows Sangster (2022) and Chesser et al. (2023) in adopting Eurasian Goshawk for A. gentilis.

Northern Black-throated Trogon Trogon tenellus, Choco Black-throated Trogon Trogon cupreicauda, and Atlantic Black-throated Trogon Trogon chrysochloros are split from Amazonian Black-throated (formerly Black-throated) Trogon Trogon rufus (Clements 2007:213–214)

Summary: Trogon diversity in South America has increased by three recognized species, tentatively called Northern, Choco, Atlantic, and Amazonian Black-throated Trogons. None of these overlap in range and identification should not be affected.

Details: Originally described as multiple species, the Black-throated Trogon Trogon rufus has been treated as a polytypic species since several forms were lumped by Cory (1919). A comprehensive integrative taxonomic study (Dickens et al. 2021) showed deep genetic divergence between trans- and cis-Andean taxa, as well as moderate divergence between birds from the Atlantic Forest of southeastern Brazil and the widespread Amazonian/Guianan shield taxa, that is largely concordant with vocal and morphological differentiation. This has now led to its treatment by SACC (https://www.museum.lsu.edu/~Remsen/SACCprop921.htm) and WGAC as four species, the monotypic T. tenellus of Middle America to far northern Colombia; T. cupreicauda from the Chocó region of Colombia to northwestern Ecuador; the polytypic T. rufus, including the intergrading taxa sulphureus of West Amazonia and amazonicus of East Amazonia, plus rufus of the Guianan shield; and the mainly southeastern Brazilian T. chrysochloros, including the isolated, highly endangered, recently described and moderately distinctive (but not readily diagnosed) muriciensis of Alagoas, northeastern Brazil.

English names: Because of a lack of resolution on English names by SACC until recently, the English names tentatively adopted here for the eBird/Clements Checklist are geographic descriptors compounded with “Black-throated” to distinguish them from other similarly named trogons. SACC names now finalized (SACC proposal 921e–x) that differ from the above are Graceful Trogon for T. tenellus of Middle America and Kerr’s Trogon for T. cupreicauda of the Chocó.

West African Pied Hornbill Lophoceros semifasciatus is split from African Pied (now Congo Pied) Hornbill L. fasciatus (Clements 2007:229)

Summary: The West African Pied Hornbill is now considered a separate species from Congo Pied Hornbill. Identification is likely to be a challenge only in south-eastern Nigeria from where hybrids are known.

Details: Originally described as separate species, the Congo Pied Lophoceros fasciatus and West African Pied Hornbill L. semifasciatus differ in bill and tail coloration characters but were found to hybridize in south-eastern Nigeria (Marchant 1953), leading to their long-time treatment as a single species. del Hoyo and Collar (2014) split semifasciatus on the basis of their morphological differences and a “probably broad zone of hybridization in SE Nigeria and SW Cameroon.” Louette (1981), however, found no intergrade specimens in Cameroon, and this together with the evidence from the ML photo archive, suggests there is no more than a narrow hybrid zone. Thus the HBW/BLI split of L. semifasciatus is agreed-upon by WGAC and followed by Clements et al. (2023) and Gill et al. (2023, IOC v.13.2).

English names: The English names adopted are the previously used group names West African Pied Hornbill vs. Congo Pied Hornbill, which aligns with HBW and BirdLife International (2022) and Gill et al. (2023, IOC v.13.2).

Eastern Long-tailed Hornbill Horizocerus cassini is split from White-crested (now Western Long-tailed) Hornbill H. albocristatus (Clements 2007:229)

Summary: The forests of western Africa now have another endemic species, the Western Long-tailed Hornbill, distinguished from Eastern Long-tailed Hornbill by its more extensively white head and lack of white wing spots.

Details: Although morphologically strikingly distinct from H. albocristatus in several characters (summarized in del Hoyo and Collar 2014), H. cassini was not recognized to science until Finsch (1903) carried out a detailed comparative study. Nevertheless, they were long treated as conspecific (e.g., Peters 1945, Wolters 1976) until split by del Hoyo and Collar (2014). Of the three taxa united in H. albocristatus, the two most dissimilar in multiple respects (macrourus and cassini) appear to be essentially parapatric, and hence the two-species treatment advocated by HBW and BirdLife International (2022) is adopted by WGAC and followed by Clements et al. (2023).

English names: The previously used English name for the parent species in the eBird/Clements Checklist was White-crested Hornbill, but for alignment with HBW and BirdLife International (2022) the eBird/Clements Checklist now uses the equally apt daughter species names Eastern Long-tailed Hornbill for H. cassini and Western Long-tailed Hornbill for H. albocristatus.

Eastern Dwarf Hornbill Horizocerus granti is split from Black Dwarf (now Western Dwarf) Hornbill H. hartlaubi (Clements 2007:229)

Summary: The Congo River separates two very distinct forms of Black Dwarf Hornbill, now recognized as separate species, Eastern and Western Dwarf Hornbill.

Details: Horizocerus granti was originally described as a distinct species by Hartert (1895), but has long been treated as a subspecies of the Black Dwarf Hornbill H. hartlaubi (e.g., Peters 1945). The several morphological differences between these taxa (e.g., Hartert 1895, del Hoyo and Collar 2014) appear consistent with a parapatric distribution across the Congo River. Thus, WGAC and Clements et al. (2023) agrees with the HBW and BirdLife International (2022) treatment of H. granti as specifically distinct.

English names: The English names Western Dwarf Hornbill H. hartlaubi and Eastern Dwarf Hornbill H. granti are used as these combine more familiar elements of the name with geographic descriptors than do the names used in HBW and BirdLife International (2022).

Blue-eared Barbet Psilopogon cyanotis is split fromBlack-eared (formerly Blue-eared) Barbet P. duvaucelii (Clements 2007:239)

Summary: The black-eared forms of Malaysia to Borneo long treated within Blue-eared Barbet are now treated as a separate species, the Black-eared Barbet. True Blue-eared Barbets are now restricted to southern and southeast Asia north of Malaysia.

Details: Blyth (1847) described Psilopogon cyanotis of southeast Asia based on its conspicuously different facial coloration from the Malaysian forms P. duvaucelii, but these have long been treated as conspecific (e.g., Peters 1945 and subsequent authors). The position taken by del Hoyo and Collar (2014) that P. cyanotis should be treated as a distinct species is supported by a seemingly narrow hybrid zone between the cyanotis and duvaucelii subspecies groups in southernmost Thailand based on ML images, and WGAC follows this treatment as separate species. The two groups are very similar if not identical vocally, as is the previously split allopatric P. australis of Java and Bali, which differs even more in facial coloration and is deeply diverged on mtDNA from P. duvaucelii (den Tex and Leonard 2013).

English names: The English name Black-eared Barbet for P. duvaucelii is apt and aligns with that of HBW and BirdLife International (2022); Blue-eared Barbet is now restricted to the most widely distributed daughter species, and the only one with blue ear-coverts.

Necklaced Woodpecker Dryobates pernyii is split from Crimson-breasted (now Crimson-naped) Woodpecker D. cathpharius (Clements 2007:251)

Summary: The former Crimson-breasted Woodpecker of the Himalayas and Chinese mountain ranges is now considered two species. Of these, the Crimson-naped Woodpecker is found mainly in the mountains of South Asia, while the Necklaced Woodpecker is found mostly in China’s mountains.

Details: Dryobates cathpharius and D. pernyii were considered separate species until lumped without rationale by Vaurie (1959). Several plumage differences (as outlined by del Hoyo and Collar 2014, who considered them separate species) between the pernyii and nominate groups exceed those shown between other pied woodpecker species pairs. They appear to be parapatric or nearly so across the Himalayas of northern Myanmar, and ML images suggest that earlier confusion in the literature about head plumage characters (e.g., Vaurie 1959 in his description of ludlowi) may relate to artifacts of specimen preparation, as well as the resemblance of immature male D. cathpharius to adult male D. pernyii. Thus, the WGAC, Gill et al. (2023, IOC v.13.2), and Clements et al. (2023) have adopted the split of the D. pernyii group.

English names: The English names Necklaced Woodpecker for D. pernyii and Crimson-naped Woodpecker for D. cathpharius highlights their most distinctive characteristics, and avoids the confusing previously used names.

Malabar Flameback Chrysocolaptes socialis is split from Greater Flameback C. guttacristatus (Clements 2007:260)

Summary: Although appearing very like the Greater Flameback, the Malabar Flameback of India’s Western Ghats differs so much in voice and drumroll that it clearly requires treatment as a separate species.

Details: The flameback woodpecker of the Western Ghats, southwestern India was long known as Chrysocolaptes guttacristatus delesserti, but this name was shown not to be applicable to this form. It was then thought to be identical to Malaysian Chrysocolaptes guttacristatus chersonesus (Whistler 1934), now treated as C. g. indomalayicus, the name with priority. Koelz (1939) however recognized that Western Ghats birds differ from Malaysian ones and hence described C. guttacristatus socialis, which has until recently been considered a poorly marked form of C. guttacristatus. Despite their plumage similarity to the Himalayan nominate C. guttacristatus and the fact that flamebacks generally have very similar acoustic signals, vocalizations and drumrolls of C. guttacristatus and C. socialis have been shown to differ considerably (Rasmussen and Anderton 2012, Abhirami et al. 2021), and were thus treated as separate species by Gill et al. (2022, IOC v.12.1). The WGAC and Clements et al. (2023) have now concluded that socialis is better treated as a distinct species. The southern distributional limits of guttacristatus are poorly known and a newly found potential contact zone (based on eBird reports) in areas between the southern Western Ghats and southern Eastern Ghats remains to be studied.

English names: The apt English name Malabar Flameback for C. socialis has a long history of usage and was resurrected by Rasmussen and Anderton (2012), where originally split, and aligns with Gill et al. (2022, IOC v.12.1). The familiar name Greater Flameback is retained for the much more widely distributed C. guttacristatus.

Buff-rumped Woodpecker Meiglyptes grammithorax is split from Zebra (formerly Buff-rumped) Woodpecker M. tristis (Clements 2007:260)

Summary: The Zebra Woodpecker is now yet another rare endemic to Java. It remains little-known and its vocalizations especially need documentation.

Details: Meiglyptes grammithorax of the Malayan region was originally described as a separate species in 1862, long after the 1821 description of M. tristis, although tristis even then was seemingly much rarer (Malherbe 1862) and with a much more limited distribution, being restricted to Java. Hesse (1912) treated grammithorax as a subspecies of tristis, however, and this has been followed since, until split by del Hoyo and Collar (2014). Several differences in plumage were outlined by del Hoyo and Collar (2014) and the two taxa may differ vocally, but further recordings of tristis and analyses will be needed to substantiate this. The marked plumage differences between grammithorax and the rare Javan endemic tristis have led the WGAC, followed by Clements et al. (2023) and Gill et al. (2023, IOC v.13.2), to agree with their treatment as two species.

English names: The English name Zebra Woodpecker for Javan M. tristis suggested by Eaton et al. (2016) highlights its bolder barring and aligns with Gill et al. (2023, IOC v.13.2). The much more widely distributed daughter species M. grammithorax retains the apt and familiar name Buff-rumped Woodpecker.

Fine-banded Woodpecker Campethera taeniolaema is split from Tullberg’s Woodpecker C. tullbergi (Clements 2007:249)

Summary: The Fine-banded Woodpecker of East African mountains is restored to species status due to its plumage and genetic distinctness from the Tullberg’s Woodpecker of West African mountains.

Details: Originally described as a separate species, the Campethera taeniolaema group of taxa had been treated as specifically distinct for many years (e.g., Peters 1948) but was lumped by White (1965) and this treatment was widely followed (e.g., Short 1982, Fry et al. 1988), although not by the first few editions of the Clements Checklist. However, the West African montane Campethera tullbergi and the two currently recognized East African taxa of the taeniolaema group are very broadly allopatric and differ dramatically in several morphological characters (as noted in del Hoyo and Collar 2014, who split them). Comparative data are lacking for acoustic characters for these evidently quiet birds, but they are relatively deeply diverged genetically compared with some other congeneric recognized species pairs (Fuchs et al. 2017a), and this in combination with the marked plumage differences has led the WGAC and Clements et al. (2023) to agree they are better treated as separate species.

English names: The English name Fine-banded Woodpecker is appropriate and well-established for C. taeniolaema, leaving Tullberg’s Woodpecker for C. tullbergi.

Citron-crested Cockatoo Cacatua citrinocristata is split from Yellow-crested Cockatoo C. sulphurea (Clements 2007:130)

Summary: The southeastern Indonesian island of Sumba has another endemic species, the distinctively colored and now endangered Citron-crested Cockatoo.

Details: The original description of Cacatua citrinocristata was from a zoo specimen and was extremely brief, but citrinocristata was then and for many years subsequently considered a distinct species from C. sulphurea. It was however lumped with C. sulphurea (e.g., Peters 1937, Mayr 1944), and this treatment was generally followed until recently. Its morphology is distinctive in several respects (most of these enumerated in Collar and Marsden 2014), including in juvenile bill coloration (Schliebusch and Schliebusch 2001), despite the fact that its distribution is (at least historically) surrounded by much more homogeneous forms of C. sulphurea. Thus, WGAC and Clements et al. (2023) join Gill and Donsker (2012; v.3.1), Eaton et al. (2016), and HBW and BirdLife International (2022) in considering C. citrinocristata a full species.

English names: The English name Citron-crested Cockatoo for C. citrinocristata is familiar from long use elsewhere, and aligns with HBW and BirdLife International (2022) and Gill and Donsker (2012; v.3.1). We retain the familiar name Yellow-crested Cockatoo for the widespread though now generally rare C. sulphurea.

Comoro Black Parrot Coracopsis sibilans is split from Lesser Vasa Parrot C. nigra (Clements 2007:141)

Summary: The Comoro Islands of Grand Comoro and Anjouan (west of Madagascar) now have an endemic parrot species, the rather small, gray-brown Comoro Black Parrot.

Details: Coracopsis sibilans of the Comoros was originally described as a full species, but has long been treated as a subspecies of C. nigra (e.g., Peters 1937), and this has been widely followed until split by del Hoyo and Collar (2014). Seychelles barklyi has been treated by some as a junior synonym of sibilans (Collar 1997), but genetic analysis has shown they are not even sister taxa (Kundu et al. 2011), and their similarity is now believed to be due to convergence (Safford and Hawkins 2013). Comoros C. sibilans is much smaller than C. nigra of Madagascar, differs in multiple plumage characters (outlined by del Hoyo and Collar 2014), and is moderately diverged in mtDNA (Kundu et al. 2011, Jackson et al. 2016). The unique mating behavior of vasa parrots, which involves the insertion of the male’s large cloacal protuberance (Wilkinson and Birkhead 1995), suggests that such substantial size differences would serve as a pregametic isolating mechanism, and thus WGAC and Clements et al. (2023) agree with HBW and BirdLife International (2022) and Gill et al. (2021, IOC v.11.2) in considering C. sibilans an independent species. It is restricted to montane forest, and it is relatively rare on Anjouan (Safford and Hawkins 2013; eBird data).

English names: The English name Comoro Black Parrot for Coracopsis sibilans avoids confusion with Greater Vasa Parrot C. vasa comorensis and aligns with Gill et al. (2021, IOC v.11.2), while Lesser Vasa Parrot remains appropriate for the more widely distributed C. nigra.

Sumba Eclectus Eclectus cornelia, Tanimbar Eclectus E. riedeli, and Papuan Eclectus E. polychloros are split from Moluccan Eclectus (formerly Eclectus Parrot) E. roratus (Clements 2007:139)

Summary: Four species are now recognized in the Eclectus Parrot complex. Each occurs in a separate island group from eastern Indonesia through northern Australia, and some are likely threatened by trade.

Details: Six forms of the genus Eclectus were originally described as full species, and of these, four form major groups on plumage, size, and biogeography (a fifth is of unknown provenance). They have all long been treated as a single species (e.g., Peters 1937), with surprisingly little dispute among subsequent authors despite the great amount of variation encompassed. The mtDNA phylogeny of Braun et al. (2017) showed deep mitochondrial divergence congruent with the four major plumage groups of Eclectus, leading WGAC, HBW and BirdLife International (2022), and Clements et al. (2023) to treat these as four separate species.

English names: English names adopted for the splits in the genus Eclectus reflect the geographic distribution of each daughter species, and Eclectus becomes the English group name.

Simeulue Parrot Psittinus abbotti is split from Blue-rumped Parrot P. cyanurus (Clements 2007:137)

Summary: The small island of Simeulue off northwestern Sumatra now has another endemic bird species, the Simeulue Parrot.

Details: Richmond (1902) described Psittinus abbotti of Simeulue Island (west of northern Sumatra) to science, though without explicitly comparing it to P. cyanurus. Another taxon, this one described as a subspecies, from the Mentawai Islands just to the south was said to be “decidedly larger” than P. cyanurus but otherwise very similar (Oberholser 1912). Riley (1929) also considered abbotti a separate species, terming it “very distinct”. However, abbotti has long been treated as a subspecies of P. cyanurus, e.g., by Peters (1937).

Several striking differences in plumage in both sexes and a substantial size difference, with abbotti being notably larger (given in support of the split by del Hoyo and Collar 2014), exist between P. abbotti (endemic to Simeulue and apparently the neighboring islet Siumat) and the widespread P. cyanurus, which is otherwise more homogeneous in plumage. Putative vocal differences for abbotti (relative to cyanurus) were given as “more strident, less musical” in Eaton et al. (2016) remain to be well-documented, but WGAC and Clements et al. (2023) join Gill et al. (2021, IOC v.11.2) and HBW and BirdLife International 2022 in considering P. abbotti better treated as a full species.

English names: The English name Simeulue Parrot for Psittinus abbotti refers to its island of endemism and has already been adopted elsewhere (Eaton et al. 2016, HBW and BirdLife International 2022, Gill et al. 2021, IOC v.11.2). The name Blue-rumped Parrot is unchanged for the much more widespread and familiar P. cyanurus.

Blue-backed Parrot Tanygnathus everetti is split from Azure-rumped Parrot T. sumatranus (Clements 2007:138)

Summary: The Blue-backed Parrot of the Philippines is now considered yet another endangered endemic species to the archipelago. The Azure-rumped Parrot remains common in some areas of Sulawesi.

Details: Tanygnathus everetti of the Philippines was originally described as a full species, though without explicit comparison to T. sumatranus of the Sulawesi region (Tweeddale 1877), and in any case both seem to have been described from female individuals, which show few differences. The two taxon groups have long been lumped (e.g., Peters 1937, where known as Tanygnathus mulleri). Arndt et al. (2019) detailed numerous though subtle plumage and soft part color differences between the Philippine T. everetti and Sulawesi region T. sumatranus groups. These groups also showed a roughly comparable level of mtDNA divergence to that between a universally recognized species pair in Tanygnathus (Arndt et al. 2019). WGAC and Clements et al. (2023) agree with HBW and BirdLife International (2020) and Gill et al. (2022, IOC v.12.1) that the everetti group is best treated as specifically distinct. Tanygnathus everetti is now recognized as Endangered by BirdLife International.

English names: The English name Blue-backed Parrot for Tanygnathus everetti aligns with HBW and BirdLife International (2022) and Gill et al. (2022, IOC v.12.1).

Macquarie Parakeet Cyanoramphus erythrotis is split from Red-crowned Parakeet C. novaezelandiae (Clements 2007:135)

Summary: Although treated as a distinct species in this update, the extinct Macquarie Parakeet will be treated as a subspecies of Red-crowned Parakeet in future.

Details: The extinct Macquarie Parakeet has been treated as a distinct species since 2012 by Gill and Donsker (2012, IOC v.3.1) following Boon et al. (2001), but this appears to have been based on a misidentified sequence (Scofield 2005), and in the future erythrotis will be considered a subspecies of C. novaezelandiae by WGAC and Clements et al. (2012).

English names: The English name reflects the geographic provenance of this extinct form and aligns with Gill and Donsker (2012, IOC v.3.1).

Dusky-cheeked Fig-Parrot Cyclopsitta melanogenia and Black-fronted Fig-Parrot C. nigrifrons are split from Blue-fronted (formerly Orange-breasted) Fig-Parrot C. gulielmitertii (Clements 2007:134–135)

Summary: New Guinea now has three “orange-breasted” species of fig-parrot: Dusky-cheeked in the south, Black-fronted in the north, and Blue-fronted in the western Bird’s Head Peninsula.

Details: No fewer than six of the currently recognized forms long treated as C. gulielmitertii were originally described as full species, but the Peters (1937, where known as C. gulielmi III, having been named after William III) single-species treatment had been broadly adopted until the complex was split four ways by del Hoyo and Collar (2014).

Schnitker (2007) showed that the isolated Vogelkop nominate form C. gulielmitertii is distinct from other subspecies groups formerly united with it in plumage pattern and sequence, and in size. The northern and southern New Guinean subspecies groups are less obviously distinct but differ in patterns of sexual dichromatism and wing coloration that are indicative of long isolation and that are likely to act as reproductive barriers (Schnitker 2007). WGAC and Clements et al. (2023) consider these three morphological groups best treated as three full species. The separation of the northeastern amabilis group from the northwestern nigrifrons enacted in del Hoyo and Collar (2014) is not considered supportable here.

English names: English names adopted for the species-level taxa accepted here align with HBW and BirdLife International (2022) and Gill et al. (2023; v.13.1).

Stella’s Lorikeet C. stellae is splitfrom West Papuan Lorikeet Charmosyna papou(Clements 2007:135)

Summary: The beautiful West Papuan Lorikeet is a newly recognized endemic bird for the Bird’s Head of western New Guinea, while Stella’s Lorikeet is widely distributed in the remainder of the island.

Details: Charmosyna stellae was described as a separate species long after C. papou was made known to science, but was for many years treated as a subspecies group (e.g., Hartert 1930, Peters 1937). Voisin and Voisin (1997) and Beehler and Pratt (2016) considered the several striking and consistent plumage differences between the isolated Vogelkop nominate C. papou and the other forms long considered conspecific to be indicative of species status. They are substantially genetically diverged (Joseph et al. 2020, Smith et al. 2023), hence the WGAC and Clements et al. (2023) now agree with HBW and BirdLife International (2022) and Gill et al. (2021, IOC v.11.2) in treating them as two species.

English names: The English name West Papuan Lorikeet better describes the distribution of Charmosyna papou and avoids the potential confusion engendered by use of the name Papuan Lorikeet, given the specific epithet and previous usage when both taxa were united. The widely familiar name Stella’s Lorikeet for the widespread C. stellae is unchanged; it has been in use since at least Iredale (1956), Forshaw (1973), Sibley and Monroe (1990), and Juniper and Parr (1998). These names also align with Pratt and Beehler (2015), Beehler and Pratt (2016), Gregory (2017), and Gill et al. (2021, IOC v.11.2).

Biak Lorikeet Trichoglossus rosenbergii is split from Coconut Lorikeet T. haematodus (Clements 2007:131–132)

Summary: The island of Biak, already known for its highly unique biodiversity, has gained yet another endemic species, the colorful Biak Lorikeet.

Details: As with many other taxa in the Rainbow Lorikeet Trichoglossus haematodus group, T. rosenbergii of Biak Island off northwestern New Guinea was originally described as a full species. Peters (1937) however considered it just one of 22 subspecies of T. haematodus, which was thus for many years among the world’s most disparate bird species in plumage. Considerable splitting has occurred since, with most sources recognizing several species in the formerly highly polytypic T. haematodus complex, but Biak rosenbergii has only recently been split (del Hoyo and Collar 2014). In the now-much reduced Trichoglossus haematodus group, Biak rosenbergii is the most divergent in plumage, and it is also divergent in a UCE-based DNA phylogeny to a similar degree as other taxa considered species in the genus (Smith et al. 2023). Hence the WGAC agrees with HBW and BirdLife International (2022) and Gill and Wright (2006, IOC v.1.0) in considering rosenbergii a full species.

English names: The English name Biak Lorikeet is apt and already familiar for Trichoglossus rosenbergii, and the name Coconut Lorikeet remains unchanged for T. haematodus; these names align with HBW and BirdLife International (2022) and Gill and Donsker (2009, IOC v.2.2).

Black-billed Hanging-Parrot Loriculus bonapartei is split from Philippine Hanging-Parrot L. philippensis (Clements 2007:140)

Summary: The Sulu Islands of the far southern Philippines now have an endemic parrot, the tiny Black-billed Hanging-Parrot.

Details: The Philippine Hanging-Parrot Loriculus philippensis as presently constituted contains several subspecies with a diversity of plumage characteristics, and as such it is far more polytypic than any other species in the genus Loriculus. Nearly all were originally described as full species, but have been lumped together for many years (e.g., Peters 1937). The Sulu Islands form Loriculus bonapartei is the only taxon that has a blackish or dark red bill (vs. bright red in other taxa) and dark grayish feet (vs. orange in other taxa), and it was tentatively split by Allen (2020). The WGAC decision (followed by Gill et al. 2023; v.13.1 and Clements et al. 2023) was to split bonapartei and to keep Camiguin Sur camiguinensis (Tello et al. 2006, Arndt 2006) split, although neither were split by Collar (2011) or del Hoyo and Collar (2014) using their 7-point scoring system. A comprehensive study of the Loriculus philippensis complex will be needed before enacting further taxonomic splits therein.

English names: The English name chosen highlights the most distinctive feature of Loriculus bonapartei, and aligns with Allen (2020) and Gill et al. (2023; v.13.1); the name of the parent species remains Philippine Hanging-Parrot L. philippensis.

Timneh Parrot Psittacus timneh is split from Gray Parrot P. erithacus (Clements 2007:141)

Summary: The Timneh Parrot, a smaller, darker West African version of the familiar Gray Parrot is now considered a distinct species that is highly sought-after as a cagebird and is now rare in its limited range.

Details: Psittacus timneh was originally described as a distinct species from P. erithacus, as was the later-described Príncipe subspecies princeps, but all have usually been treated as conspecific (e.g., Peters 1937). However, BirdLife International and thus IUCN have considered P. timneh a full species since 2011 (https://stuartmarsden.blogspot.com/2013/12/timneh-parrot-and-grey-parrot-represent.html; https://www.parrots.org/cites/GreyParrot_FAQ.pdf; Marsden et al. 2015), as have Gill and Donsker (2014, IOC v.4.3). del Hoyo and Collar (2014) enumerated several morphological distinctions between timneh and erithacus and deep mtDNA divergence suggesting an age of 2.4 million years (Melo and O’Ryan 2007) that led these authors to split them as two species. The UCE phylogeny of Smith et al. (2023) also shows a relatively deep divergence between timneh and erithacus. They are considered to be parapatric, and a presumably feral population of P. timneh in Abidjan, Côte d’Ivoire, is said not to mix with P. erithacus (Lepperhoff 2007); further documentation needed. Hybrids produced in captivity between erithacus and timneh are scarce and difficult to produce, with one reported from 1957 (Lepperhoff 2007) and others advertised online, but published documentation of effort and any failed attempts to produce hybrids is inadequate. There is strong consensus among aviculturists that P. timneh and P. erithacus differ in temperament, with timneh being a much calmer and less demanding pet that matures more quickly and begins to speak earlier (Lepperhoff 2007), and thus avicultural demand for P. timneh has increased.

English names: The English name Timneh Parrot for Psittacus timneh has received wide usage and reflects the specific epithet; no English name change occurs to Gray Parrot P. erithacus. These names align with HBW and BirdLife International (2022) and Gill and Donsker (2014, IOC v.4.3), as well as being very widely used and familiar. In aviculture, they are often referred to as Congo Gray Parrot and Timneh Gray Parrot, and variants thereof.

Cordilleran Parakeet Psittacara frontatus is split from Scarlet-fronted Parakeet P. wagleri (Clements 2007:143)

Summary: The Cordilleran Parakeet of drier habitats from southwestern Ecuador through Peru is now considered a separate species from the Scarlet-fronted Parakeet of northern Venezuela and western Colombia.

Details: Psittacara frontatus was first described as a full species by Cabanis (1846), although there it was explicitly compared only to P. mitratus, which also occurs in Peru (the region being covered in Cabanis’ monograph), rather than P. wagleri of Venezuela and Colombia, with which it has long since been united (e.g., Peters 1937), although Ridgely and Greenfield (2001) suggested full species status may be warranted. There are several morphological differences between forms of P. frontatus and those of P. wagleri, enumerated by del Hoyo and Collar (2014) and confirmed by Donegan et al. (2016), and these seem consistent with species limits among other Psittacara. Published genetic data comparing frontatus and wagleri appear to be lacking but they might not even be sister taxa. Thus WGAC and Clements et al. (2023) join HBW and BirdLife International (2022) and Gill and Donsker (2017, IOC v.7.2) in considering P. frontatus an independent species.

English names: The English names used align with HBW and BirdLife International (2022) and Gill and Donsker (2017, IOC v.7.2).

Gray-lored Broadbill Serilophus rubropygius is split from Silver-breasted Broadbill S. lunatus (Clements 2007:264)

Summary: The Gray-lored Broadbill is now recognized as a distinct species occurring west of the Ayeyarwady (Irrawaddy) River of Myanmar and in the eastern Himalayas.

Details: Serilophus rubropygius of the eastern Himalayas to western Myanmar was described to science as a new species, but without having been explicitly compared to S. lunatus of southeast Asia (Hodgson 1839). For many years rubropygius was treated as a full species and was thought to be sympatric with S. lunatus in the Chin Hills (Garthwaite and Ticehurst 1937), though no proof of sympatry has emerged (Dekker and Dickinson 2000), and most sources at least since Peters (1951) have treated rubropygius as one of several subspecies within lunatus. Nevertheless, there appears to be ample evidence of parapatry on either side of the Irrawaddy (Ayeyarwady) River between the single western taxon rubropygius and the lunatus group, all of which differ from rubropygius conspicuously and consistently in wing coloration and especially feather shapes, as well as in bare yellow skin in the lores and bordering the bill base, lacking in rubropygius. ML images show that both taxa occur in different parts of Yunnan, southwestern China. Though the simple vocalizations of rubropygius and lunatus seem very similar, and no genetic analysis including both is yet published, the strong evidence of striking differentiation in parapatry has led WGAC and Clements et al. (2023) to agree with HBW and BirdLife International (2022) and Gill et al. (2023; v.13.2) in considering rubropygius a distinct species from the lunatus complex.

English names: The English name Gray-lored Broadbill highlights one of the best distinguishing characteristics of Serilophus rubropygius from the more widely distributed Silver-breasted Broadbill S. lunatus, which has bare yellowish lores.

North Papuan Pitta Erythropitta habenichti is split from South Papuan (formerly Papuan) Pitta E. macklotii (Clements 2007:267)

Summary: Northern New Guinea now has another endemic species, the colorful North Papuan Pitta, now split from South Papuan Pitta.

Details: As with many of the other taxa long united in the Red-bellied Pitta Erythropitta erythrogaster complex (e.g., Mayr 1979), E. habenichti was originally described as a full species in direct comparison to E. macklotii of southern New Guinea. It appears to be essentially parapatric with macklotii without known intergradation, and many species complexes divide along similar lines in north vs. south New Guinea. Thus WGAC and Clements et al. (2023) consider E. habenichti a full species.

English names: The English names North Papuan Pitta for Erythropitta habenichti and South Papuan Pitta for E. macklotii encapsulate their differential geographic distributions.

Nicobar Hooded Pitta Pitta abbotti, Minahasa Hooded Pitta P. forsteni, Eastern Hooded Pitta P. novaeguineae, and Biak Hooded Pitta P. rosenbergii are split from Western Hooded (formerly Hooded) Pitta P. sordida (Clements 2007:266–267)

Summary: The Hooded Pitta is now split into Western Hooded, Nicobar Hooded, Minahasa Hooded, Eastern Hooded, and Biak Hooded Pittas, each named for their geographical range.

Details: Several taxa long subsumed within the Hooded Pitta Pitta sordida complex (e.g., Mayr 1979) were originally described as full species, including P. abbotti of the southern Nicobar Islands; P. forsteni of the Minahasa Peninsula, northern Sulawesi; P. novaeguineae of the New Guinea region, and P. rosenbergii of Biak, off northwestern New Guinea. Each of these have been shown in integrative taxonomic analyses (Ericson et al. 2019, Rasmussen et al. 2020) to be vocally and morphologically distinct in congruence with genetic structure of the complex, and hence WGAC and Clements et al. (2023) adopt a five-species complex. One further genetic cluster identified in Ericson et al. (2019), that of the Philippines, does not have morphological or vocal support and thus is not considered speciated by WGAC or Clements et al. (2023).

English names: For each species in this complex, geographic names are compounded with “Hooded” to reduce confusion with other regional pitta species. The name Eastern Hooded Pitta for the New Guinea complex (except Biak P. rosenbergii), previously used by del Hoyo and Collar (2016), minimizes confusion with the Erythropitta pittas so is adopted here.

Northern White-fringed Antwren Formicivora intermedia is split from Southern White-fringed (formerly White-fringed) Antwren F. grisea (Clements 2007:297)

Summary: Though males look similar, females do not and the songs of the Northern White-fringed Antwren differ dramatically from the genetically distinct Southern White-fringed Antwren.

Details: As early as 1913, at least two of the northern group of taxa were described as subspecies of the former White-fringed Antwren F. grisea (e.g., Peters 1951), though with considerable uncertainty even then as to species limits largely due to the marked differences in female plumage between taxa (Cory 1913, Chapman 1914). Vocal differences have long been noted leading to suggestions that more than one species is involved (Ridgely and Tudor 1994, Zimmer and Isler 2003, Boesman 2016 [No. 46]) and some authors split the intermedia group of subspecies from the grisea group (Hilty 2003, 2021, Gill and Wright (2006, IOC v.1.0), del Hoyo and Collar 2016). Genomic data now confirm that Formicivora intermedia and F. grisea are deeply diverged genetically (Harvey et al. 2020), and thus WGAC and Clements et al. (2023) agree with Hilty (2003, 2021), HBW and BirdLife International (2022), and Gill and Wright (2006, IOC v.1.0) in recognizing the Formicivora intermedia complex as specifically distinct. A proposal is needed for SACC action.

English names: For English names, regional modifiers are compounded with “White-fringed”, as in sources as long ago as Hilty (2003) and Gill and Wright (2006, IOC v.1.0), and as previously used group names in eBird.

Boyaca Antpitta Grallaria alticola and Atuen Antpitta G. atuensis are split from Tawny Antpitta G. quitensis (Clements 2007:306)

Summary: The Boyaca Antpitta of the northern and central Colombian Andes and the Atuen Antpitta of a tiny area of the north-central Andes of Peru are now considered separate species from the more widespread Tawny Antpitta of the southern Colombian and Ecuadorian Andes. All are found at higher elevations than most other antpittas.

Details: Grallaria alticola was originally described as a full species, though without explicit comparison to any other taxon (Todd 1919), while G. atuensis has always been considered a subspecies of G. quitensis until recently, and was indeed long known only from the type specimen (Peters 1951). Differences in vocalizations between the three taxa have been known for decades, and it has been suggested that three species are involved (Krabbe and Schulenberg 2003). Boesman (2016 [No. 72]) compared then-available recordings, in which (though limited in number) differences in both song and call support the three-way split enacted by del Hoyo and Collar (2016). Genetic analyses comparing these three taxa do not appear to be available. Largely on the basis of the vocal differences, WGAC and Clements et al. (2023) join HBW and BirdLife International (2022) and Gill et al. (2023; v.13.2) in the three-species treatment of the Grallaria quitensis complex, which has not yet been considered by SACC.

English names: The English names Boyaca Antpitta for G. alticola and Atuen Antpitta for G. atuensis reflect the type localities of each daughter species, while the English name for the widespread nominate is unchanged.

Tapajos Scythebill Campylorhamphus probatus and Xingu Scythebill C. multostriatus are split from Curve-billed Scythebill C. procurvoides (Clements 2007:289)

Summary: The Curve-billed Scythebill occurs widely through much of Amazonia, while the Tapajos Scythebill of south-central Amazonia and the Xingu Scythebill of north-eastern Amazonia are now considered separate species.

Details: In 1907, Campylorhamphus multostriatus was described as a full species based on extensive comparisons with C. procurvoides (Snethlage 1907), but C. probatus has always been considered a subspecies of C. procurvoides, and by 1934 multostriatus was also included within that species (Zimmer 1934, Peters 1951). It has been known for several years that multiple species must be involved in the C. procurvoides complex (e.g., https://www.museum.lsu.edu/~Remsen/SACCprop623.htm), and two new species were described in the complex relatively recently, but these are now generally recognized as subspecies. Genetic analyses are largely congruent with known differences in vocalizations as well as to some extent morphology, leading to the recognition of three species in the Campylorhamphus procurvoides complex (del Hoyo and Collar 2016), now agreed-upon by WGAC, Gill et al. (2023; v.13.2), and Clements et al. (2023). Reconsideration of this issue by SACC is needed.

English names: English names reflect the ranges of the daughter taxa and align with HBW and BirdLife International (2022) and Gill et al. (2023; v.13.2).

Pacific Hornero Furnarius cinnamomeus and Caribbean Hornero F. longirostris are split from Pale-legged Hornero F. leucopus (Clements 2007:270)

Summary: The Pacific Hornero mainly of coastal Ecuador and northern Peru and the Caribbean Hornero of northern Colombia and Venezuela are split from the Amazonian Pale-legged Hornero.

Details: Most currently recognized taxa of the Furnarius leucopus complex (e.g., Peters 1951) were originally described as full species, and F. cinnamomeus continued to be treated as specifically distinct by Chapman (1926). Numerous more recent authors (e.g., Ridgely and Tudor 1994) have suggested or enacted splits. Differences in morphology that are largely congruent with apparent vocal (Boesman 2016 [No. 88]) and genetic divergence and paraphyly (Harvey et al. 2020) led WGAC and Clements et al. (2023) to agree with Aleixo et al. (2013), Donegan et al. (2013), del Hoyo and Collar (2016), and Gill and Wright (2006, IOC v.1.0) in enacting a three-way split. Further study is needed in the complex, as suggested by the apparently deep genetic split between Guianan and western Amazonian populations. A 2003 SACC proposal (https://www.museum.lsu.edu/~Remsen/SACCprop35.htm) did not pass pending published data.

English names: The geographically based English names for the daughter taxa align with HBW and BirdLife International (2022), Gill and Wright (2006, IOC v.1.0), and other sources.

Fawn-throated Foliage-gleaner Automolus cervinigularis is split from Ochre-throated (formerly Buff-throated) Foliage-gleaner A. ochrolaemus (Clements 2007:281)

Summary: The Fawn-throated Foliage-gleaner is a newly recognized species endemic to the Caribbean side of southern Mexico through northern Panama.

Details: Several members of the Automolus ochrolaemus complex (sensu Peters 1951) were originally described as full species, including A. cervinigularis, which however was not explicitly compared with A. ochrolaemus in the original description (Sclater 1856 (1857)), and as late as 1909 a new subspecies was described within A. cervinigularis (Ridgway 1909). However, the Peters (1951) treatment has remained dominant for many years, until A. exsertus of the Pacific slope of Costa Rica and western Panama was split (Freeman and Montgomery 2017, Chesser et al. 2018). However, vocal and genetic evidence (Smith et al. 2014) congruently shows three major groups in the A. ochrolaemus complex, with the A. cervinigularis group of Mexico through eastern Central America being vocally more similar to and genetically sister to A. exsertus than to the other group, the eastern Panamanian and South American taxa of A. ochrolaemus. Hence the cervinigularis group is also split by WGAC, Gill et al. (2023; v.13.2), and Clements et al. (2023).

English names: The English name Fawn-throated Foliage-gleaner for Automolus cervinigularis reflects its specific epithet, it is an apt descriptor, and it aligns with Gill et al. (2023; v.13.2).

Western Woodhaunter Automolus virgatus is split from Eastern (formerly Striped) Woodhaunter A. subulatus (Clements 2007:280)

Summary: The Western Woodhaunter of Central America and northwestern South America is now considered a distinct species from the Eastern Woodhaunter of the western and central Amazon and Orinoco regions.

Details: Automolus virgatus was originally described as a species in great detail, though without explicit comparison with A. subulatus (Lawrence 1867), with which it has long been considered conspecific (Peters 1951; but see Gill and Wright 2006, IOC v.1.0). However, major vocal differentiation between the A. virgatus and A. subulatus groups (Ridgely and Tudor 1994, Boesman 2016 [No. 90]) with congruent genetic divergence (Schultz et al. 2017) is considered by WGAC and Clements et al. (2023) to be strong evidence for the two-species treatment enacted by del Hoyo and Collar (2016). A 2003 SACC proposal (https://www.museum.lsu.edu/~Remsen/SACCprop40.htm) to split A. virgatus did not pass owing to insufficient published data.

English names: The English names distinguish between the regions inhabited by the two species and align with Gill and Wright (2006, IOC v.1.0).

Plain Thornbird Phacellodomus inornatus is split from Rufous-fronted Thornbird P. rufifrons (Clements 2007:277)

Summary: The Plain Thornbird of much of Venezuela is now considered a separate species from the widely disjunct Rufous-fronted Thornbird mainly of south-central parts of South America.

Details: Unlike most taxa subsumed under Phacellodomus rufifrons (sensu Peters 1951, Wolters 1977), P. inornatus was originally described as specifically distinct (Ridgway 1887) and said to be “a very distinct species” from P. rufifrons. Despite its longtime subspecies, treatment, P. inornatus has been suggested for decades to be specifically distinct based on morphology (Ridgely and Greenfield 2001), with the split enacted by Hilty (2003) and Gill and Wright (2006, IOC v.1.0). Now, vocalizations have been shown to differ (Boesman 2016 [No. 95]) and it is genetically divergent from the southern subspecies (Corbett et al. 2020), leading WGAC and Clements et al. (2023) to agree with the two-species treatment enacted by del Hoyo and Collar (2016), although further study of the complex may result in subsequent species-level changes to the taxa remaining in the rufifrons complex. A 2003 SACC proposal to split P. inornatus (https://www.museum.lsu.edu/~Remsen/SACCprop41.htm) did not pass due to insufficient published data.

English names: The English name Plain Thornbird aptly describes Phacellodomus inornatus and has a long history of use, aligning with Hilty (2003), HBW and BirdLife International (2022) and Gill and Wright (2006, IOC v.1.0).

Araguaia Spinetail Synallaxis simoni is split from White-lored Spinetail S. albilora (Clements 2007:273)

Summary: The Araguaia Spinetail is endemic to a small area in the Araguaia basin of east-central Brazil.

Details: Originally described as a full species but said to be intermediate between S. gujanensis and S. albilora (Hellmayr 1907), Synallaxis simoni does not however occur in areas intervening between those two, nor is its range contiguous with that of S. albilora. This isolated taxon from a known area of endemism differs in plumage and in vocalizations (Boesman 2016 [No. 102]), hence was split by del Hoyo and Collar (2016) and is now considered by WGAC and Clements et al. (2023) to be better treated as a full species. The issue remains to be considered by SACC.

English names: The name Araguaia Spinetail for Synallaxis simoni reflects its geographic distribution in the Araguaia Valley. A different, evidently undescribed spinetail from the same region and tentatively placed within Certhiaxis is now informally called “Tocantins Spinetail”.

Andean Laniisoma Laniisoma buckleyi is split from Brazilian Laniisoma (formerly Shrike-like Cotinga) L. elegans (Clements 2007:311–312)

Summary: The Andean Laniisoma is now considered a distinct species, though it is rare and with a scattered distribution in the Andes from Venezuela to northern Bolivia.

Details: Originally described as a full species (Sclater and Salvin 1888), Laniisoma buckleyi has often been treated as specifically distinct (e.g., Hellmayr 1929, Ridgely and Greenfield 2001, Hilty 2003, Gill and Wright 2006, IOC v.1.0), though not by influential taxonomies such as Snow (1979) and Wolters (1977). It is now known to differ from L. elegans in plumage of both sexes and in vocalizations (Boesman 2016 [No. 114]), and to be more genetically divergent than are some other related taxa considered specifically distinct (Harvey et al. 2020). WGAC and Clements et al. (2023) thus agree with the treatment of L. buckleyi as specifically distinct as in del Hoyo and Collar (2016) and previous authors. A proposal to SACC is needed on this matter.

English names: The Andean Laniisoma was formerly called Shrike-like Cotinga but it is neither a cotinga nor shrike-like, and it is relatively rarer than its southeastern Brazilian counterpart, the Brazilian Laniisoma. The names adopted by Clements et al. (2023) align with those used by Gill and Wright (2006, IOC v.1.0).

Cryptic Becard Pachyramphus salvini is split from Black-and-white Becard P. albogriseus (Clements 2007:347)

Summary: The Cryptic Becard is yet another endemic species mainly found from western Colombia through Ecuador and northwestern Peru.

Details: Pachyramphus salvini was originally named as a full species (though with a different, preoccupied name), but has long been treated as conspecific with P. albogriseus (e.g, Snow 1979). It has now been shown conclusively that P. salvini is not even a sister taxon of P. albogriseus, though they appear very similar (albeit with multiple diagnostic differences), and it is also vocally different (Musher and Cracraft 2018, Musher et al. 2023). Hence WGAC and Clements et al. (2023) agree with SACC (https://www.museum.lsu.edu/~Remsen/SACCprop955.htm) and Gill et al. (2023; v.13.2) in treating P. salvini as a separate species, as recommended by Musher et al. (2023). For subspecies issues, see Subspecies Changes section.

English names: TheEnglish name of the much more widespread P. albogriseus remains Black-and-white Becard, while the English name of the species with which it was confused for so long, P. salvini, becomes Cryptic Becard in alignment with SACC and Gill et al. (2023, v.13.2).

Atlantic Royal Flycatcher Onychorhynchus swainsoni is split from Tropical Royal (formerly Royal) Flycatcher O. coronatus (Clements 2007:331)

Summary: Atlantic Royal Flycatcher is yet another species endemic to Brazil’s already endemic-replete southeastern rainforest.

Details: Each of the major geographical and plumage groups of Onychorhynchus were originally described as distinct species, but have generally been united as a single species by most authors (e.g., Traylor 1979a), although numerous suggestions have been made since regarding splits within the genus, and Gill and Wright (2006, IOC v.1.0) recognized four species in Onychorhynchus. However, vocalizations appear to be similar for all except O. swainsoni (Sample et al. 2023), and much the deepest divergence is between swainsoni and the others (Harvey et al. 2020). Reyes et al. (2023), which appeared after the WGAC decision was made, strongly supports the split of the anciently diverged O. swainsoni but also suggests several further splits.

English names: The name Atlantic Royal Flycatcher aligns with del Hoyo and Collar (2016) and Gill and Wright (2006, IOC v.1.0), and the name Tropical has been coined for the other taxa combined as a single species.

Western Olivaceous Flatbill Rhynchocyclus aequinoctialis is split from Eastern Olivaceous (formerly Olivaceous) Flatbill R. olivaceus (Clements 2007:330)

Summary: Western Olivaceous Flatbill of eastern Panama through western Amazonia is split from the Eastern Olivaceous Flatbill of the Guianan Shield to southeastern Brazilian. These species as recognized here overlap broadly in western Amazonia.

Details: Described as a full species by Sclater (1858) with reference to Rhynchocyclus olivaceus, R. aequinoctialis has long been treated as a subspecies group of R. olivaceus (e.g., Traylor 1979b). However, major vocal differences as noted by Boesman (2016 [No. 120]) were considered by del Hoyo and Collar (2016) a major part of their justification to split them. Simões et al. (2021) showed that there is further complexity in this system that might lead to further splits, and described a new species R. cryptus Simões et al., 2021 that is broadly sympatric with R. olivaceus in Amazonian Peru and western Brazil; R. cryptus is here considered a subspecies of R. aequinoctialis. WGAC and Clements et al. (2023) agree with del Hoyo and Collar (2016) and Gill et al. (2023, IOC v.13.2) that at least the split between olivaceus and aequinoctialis is well-justified. Proposals to SACC and NACC (where the complex occurs only in eastern Panama) on this matter are needed.

English names: The English names Western and Eastern Olivaceous Flatbill accord with their geography and already have considerable familiarity through usage in del Hoyo and Collar (2016).

Bacan Myzomela Myzomela batjanensis is split from Sulawesi Myzomela M. chloroptera (Clements 2007:558)

Summary: The Bacan Myzomela can only be found high on the inaccessible mountain slopes of Bacan in the Moluccas of eastern Indonesia, so has only been seen by a few indefatigables.

Details: In the original description of Myzomela batjanensis of Bacan Island in the Moluccas, Hartert (1903) thoroughly compared it to several other taxa including M. chloroptera of Sulawesi, although he also suggested the differences might be subspecific. Indeed, batjanensis and numerous other taxa including chloroptera were long united with M. sanguinolenta (e.g., Salomonsen 1967). However, Eaton et al. (2016) and del Hoyo and Collar (2016) considered the isolated montane M. batjanensis to be a separate species on the basis of plumage and evidently distinct voice, despite small sample sizes of vocalizations.

English names: The English name Bacan Myzomela adopts the modern spelling of the island and aligns with HBW and BirdLife International (2022) and Gill et al. (2022; IOC v.12.1), as well as with Eaton et al. (2016).

Long-billed Myzomela Myzomela longirostris is split from Red-collared Myzomela M. rosenbergii (Clements 2007:559)

Summary: The Long-billed Myzomela is now considered an endemic species to the mountains of Goodenough Island, southeast of New Guinea.

Details: First described by Mayr and Rand (1935) as a subspecies of M. rosenbergii, the authors called it “very distinct” even though they had no adult female specimen, now known to have a much more distinct plumage than the male. Myzomela longirostris has continued to be treated as a subspecies of Myzomela rosenbergii (e.g., Salomonsen 1967) until split by del Hoyo and Collar (2016) based on the distinctive plumage of female longirostris and that taxon’s much larger size, especially in bill length. WGAC, Clements et al. (2023), and Gill et al. (2021, IOC v.11.2) now agree with HBW and BirdLife International (2022) in adopting this split.

English names: The English name Red-collared Myzomela is retained by the widely distributed M. rosenbergii, while Long-billed Myzomela, adopted for M. longirostris, aligns with HBW and BirdLife International (2022) and Gill et al. (2021, IOC v.11.2) and echoes the species’ scientific name.

Western Crested Berrypecker Paramythia olivacea is split from Eastern Crested (formerly Crested) Berrypecker P. montium (Clements 2007:545)

Summary: The Western Crested Berrypecker of West Papua is now considered a separate species from Eastern Crested Berrypecker of Papua New Guinea.

Details: Although originally described as a subspecies of Paramythia montium, P. olivacea differs in several morphological characters, most notably crest shape. These birds are quiet and have not yet been included together in molecular phylogenetic analyses. del Hoyo and Collar (2016) and Beehler and Pratt (2016) enumerated morphological distinctions that led them to independently split P. olivacea from P. montium. WGAC, Clements et al. (2023), and Gill et al. (2021, IOC v.11.2) agree with the aforementioned authors in splitting P. olivacea.

English names: The English names adoptedalign with those used in Beehler and Pratt (2016), HBW and BirdLife International (2022), and Gill et al. (2021, IOC v.11.2), and clearly reflect their relative distributions within New Guinea.

Wetar Oriole Oriolus finschi is split from Timor Oriole O. melanotis (Clements 2007:567)

Summary: The Wetar Oriole is now treated as a distinct species from the Timor Oriole.

Details: Oriolus finschi of Wetar Island was originally described as a full species (Hartert 1904), but with the author’s caveat that probably it and several other taxa would rank as subspecies of a single species. Indeed, O. finschi has long been considered a subspecies of O. melanotis of Timor (Greenway 1962), although most other Wallacean Oriolus are now considered separate species. del Hoyo and Collar (2016) and Eaton et al. (2016) split O. finschi based on its pronounced morphological and vocal differences from O. melanotis (Boesman 2016 [No. 160]), and since then finschi and melanotis have been found to be deeply divergent molecularly (Jønsson et al. 2019). WGAC, Clements et al. (2023) and Gill et al. (2021, IOC v.11.2) now align with HBW and BirdLife International (2022) in treating O. finschi as an independent species.

English names: The English names adopted align with those used by Gill et al. (2021, IOC v.11.2), HBW and BirdLife International (2022), and Eaton et al. (2016).

Ventriloquial Oriole Oriolus consobrinus is split from Dark-throated Oriole O. xanthonotus (Clements 2007:567–568)

Summary: The Ventriloquial Oriole of Sabah and northeastern Kalimantan, northeastern Borneo and the Palawan island group of the southwestern Philippines is now considered a full species.

Details: Originally named as a distinct species, Oriolus consobrinus of northeastern Borneo was already being treated as a subspecies of the Malayan region O. xanthonotus by 1922 when the closely similar Palawan form persuasus was described as a subspecies (Bangs 1922). In addition, the Philippine forms now considered Philippine Oriole Oriolus steerii were also included under O. xanthonotus by e.g., Greenway (1962), though in recent years O. steerii and its subspecies has not been included in the complex. A new integrative taxonomic analysis (Rheindt et al. 2022) found that the consobrinus/persuasus and xanthonotus clades are paraphyletic with O. steerii, and that morphological and vocal data strongly support the split of O. consobrinus, with persuasus as a subspecies. Thus, WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.2) now align in treating O. consobrinus as an independent species. The western range limits of O. consobrinus and nature of any interactions there with O. xanthonotus remain to be determined.

English names: The English names Dark-throated Oriole for the widespread O. xanthonotus and Ventriloquial Oriole for the mainly Sabah and Palawan forms O. consobrinus reflect their vocalizations and align with the group name used in Eaton et al. (2021), as well as the species name proposed in Rheindt et al. (2022) and used in Gill et al. (2023, IOC v.13.2).

Black-and-crimson Oriole Oriolus consanguineus is split from Javan (formerly Black-and-crimson) Oriole O. cruentus (Clements 2007:569)

Summary: Java now has an endemic oriole species, the Javan Oriole, which is threatened due to the cagebird trade. The Black-and-crimson Oriole has a much more extensive range, and remains generally common.

Details: Both O. consanguineus of Malaysian and Sumatran mountains and the Bornean montane form O. vulneratus were originally described as full species, though all have long been lumped under O. cruentus (e.g., Greenway 1962). del Hoyo and Collar (2016) showed that the now-rare Javan cruentus differs in numerous characters from the others, and they thus considered them specifically distinct. Vocalizations of cruentus are very poorly known but seem to differ in frequency range at least. There is surprisingly deep genetic divergence between the consanguineus group and cruentus (Jønsson et al. 2019), but the Bornean form vulneratus (which also differs from other taxa in several plumage characters; del Hoyo and Collar 2016), is closely related to and in the same genetic cluster as consanguineus. Eaton et al. (2021) agreed with the treatment of cruentus as an independent species (del Hoyo and Collar 2016), as do WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.2).

English names: The English names adopted, Javan Oriole for the endemic O. cruentus and Black-and-crimson Oriole for the widespread O. consanguineus complex, align with usage of del Hoyo and Collar (2016), Eaton et al. (2021), and Gill et al. (2023, IOC v.13.2).

White-gorgeted Fantail Rhipidura coultasi is split from White-winged (formerly Cockerell’s) Fantail R. cockerelli (Clements 2007:569)

Summary: The island of Malaita, in the southeastern Solomon Islands, now has a second endemic species of fantail, the White-gorgeted Fantail.

Details: As with most members of the Rhipidura cockerelli complex (e.g., Watson and Mayr 1986, almost all of which were named by Rothschild and Hartert or Mayr), R. coultasi of Malaita, in the southeastern Solomon Islands, was originally named as a subspecies (Mayr 1931a), though with the caveat “[t]his very distinct subspecies shows several peculiarities not found in any of the other forms of the species.” Dutson (2011) suggested coultasi might be a separate species, and it was split by del Hoyo and Collar (2016); both authorities called attention to its much larger size. No relevant genetic analyses are available but a good recording of both song and calls from Malaita suggests strong vocal differences from its erstwhile conspecifics. Further species-level adjustments may be necessary in the R. cockerelli group but at present WGAC and Clements et al. (2023) agree with del Hoyo and Collar (2016) in recognizing R. coultasi as a full species.

English names: The English names White-winged Fantail for the cockerelli group and White-gorgeted Fantail for coultasi are appropriate and have previously been used by del Hoyo and Collar (2016).

Supertramp Fantail Rhipidura semicollaris is split from Arafura Fantail R. dryas (Clements 2007:471)

Summary: The former “Rufous Fantails” of the Lesser Sundas and islands west of New Guinea form a group now called Supertramp Fantail, while those of southern New Guinea and northern Australia comprise the Arafura Fantail.

Details: As with a great many taxa in the Rhipidura rufifrons complex (e.g., Watson and Mayr 1986), R. semicollaris was originally described as a full species. Until recently, however, R. rufifrons sensu lato has been one of the most polytypic bird species in the world. del Hoyo and Collar (2016) began to rectify this situation by treating 11 subspecies as Arafura Fantail R. dryas. Eaton et al. (2016), however split most of the Indonesian taxa except for those of the north Moluccas as Supertramp Fantail R. semicollaris, with 9 subspecies, based on plumage and song. As now treated by WGAC and Clements et al. (2023), the Arafura Fantail R. dryas is now limited to two subspecies in northwestern Australia and southern New Guinea. The move of southern New Guinea subspecies streptophora from the semicollaris group to a subspecies of R. dryas follows Beehler and Pratt (2016). Genomic data (Klicka et al. 2023) bolster the case for the species-level treatment followed here.

English names: The English names adopted are those used in Eaton et al. (2016).

Gilolo Fantail R. torrida, Louisiade Fantail R. louisiadensis, Santa Cruz Fantail R. melaenolaema, Micronesian Rufous Fantail R. versicolor, and Solomons Rufous Fantail R. rufofronta are split from Australian Rufous (formerly Rufous) Fantail R. rufifrons (Clements 2007:471)

Summary: The “Rufous Fantail” Rhipidura rufifrons complex has been further split into the Gilolo Fantail of the northern Moluccas, eastern Indonesia; Louisiade Fantail of islands southeast of New Guinea; Santa Cruz Fantail of that southeastern Solomon Island group; Micronesian Rufous Fantail of the Marianas and Yap in the Caroline Islands; Solomons Rufous Fantail of most of the Solomon Islands; and Australian Rufous Fantail of eastern Australia.

Details: Each of the six groups discussed here were originally described as a full species, before being united in the megadiverse Rufous Fantail complex (e.g., Watson and Mayr 1986). Now, genomic data (Klicka et al. 2023) in combination with plumage and bioacoustics have led WGAC followed by Clements et al. (2023) to divide this group into six species: a monotypic R. torrida of the northern Moluccas; monotypic louisiadensis of the D’Entrecasteaux and Louisiade islands off southeastern New Guinea; three subspecies of R. melaenolaema from the Santa Cruz Group of the southeastern Solomon Islands; four subspecies of R. versicolor from Micronesia; seven subspecies of R. rufofronta from the Solomon Islands; and two subspecies of R. rufifrons from eastern Australia. Further study may result in the recognition of additional species in the complex.

English names: For each of the daughter species, Clements et al (2023) has adopted an appropriate geographical name, and where confusion is possible, added the modifier “Rufous”.

Guadalcanal Fantail Rhipidura ocularis is split from Bougainville (formerly Brown) Fantail R. drownei (Clements 2007:470)

Summary: Guadalcanal Fantail and Bougainville Fantail are now considered single-island endemics to the mountains of the Solomon Islands.

Details: Both Rhipidura drownei of Guadalcanal and R. ocularis of Bougainville were named to science by Mayr (1931) in the same publication, with the plumage differences of the latter described in detail but nevertheless at the subspecies level, although the two forms are isolated in mountains far apart in the Solomon Islands. del Hoyo and Collar (2016) separated them specifically based on numerous plumage distinctions, and now good series of recordings of both suggest they are very different vocally, leading WGAC and Clements et al. (2023) to agree with species status for both.

English names: The geographically apt English names used by del Hoyo and Collar (2016) are adopted here.

Vanuatu Streaked Fantail Rhipidura spilodera and Fiji Streaked Fantail R. layardi are split from New Caledonian Streaked (formerly Streaked) Fantail R. verreauxi (Clements 2007:470)

Summary: The New Caledonian group and the islands of Vanuatu and Fiji now each have an endemic species of fantail, each named after their area of endemism.

Details: Each of the five subspecies long recognized in the Rhipidura spilodera complex (e.g., Watson and Mayr 1986) was originally named as a full species. Of these, those from the major island groups (New Caledonia, Vanuatu, and Fiji) each have notable plumage distinctions, with further variability among the Fijian races that led del Hoyo and Collar (2016) to split R. spilodera four ways. Available recordings suggest striking vocal differences but larger samples and analysis is required to confirm this. The WGAC consensus is that there was little justification for the original lump of these taxa from disparate areas, and thus a three-way split is adopted, with further study being required to adopt any further splits within Fiji.

English names: The geographically apt English names used by del Hoyo and Collar (2016) are adopted here.

Short-tailed Drongo Dicrurus striatus and Palawan Drongo D. palawanensis are split from Hair-crested Drongo D. hottentottus (Clements 2007:­­579)

Summary: The Short-tailed Drongo of the southern Philippines, and the Palawan Drongo of the southwestern Palawan group of islands are now considered distinct species.

Details: As with most taxa long subsumed in the Dicrurus hottentottus complex (e.g., Vaurie 1962), both D. striatus and D. palawanensis were originally named as full species. The molecular phylogeny of Shakya et al. (2020) is consistent with treating striatus plus samarensis as subspecies of D. balicassius rather than D. hottentottus, but the difference in tail shape argues against this treatment (previously adopted by Gill et al. 2023). Dicrurus striatus was tentatively split by del Hoyo and Collar (2016), followed by Allen (2020) and Gill et al. (2023, IOC v.13.2) and WGAC and Clements et al. (2023) adopt this treatment. Dicrurus palawanensis (plus probably cuyensis) is shown in Shakya et al. (2020) to be better treated as a full species, and this is also followed by WGAC and Clements et al. (2023).

English names: The English names follow those in use in del Hoyo and Collar (2016), Allen (2020), and Gill et al. (2023, IOC v.13.2).

Obi Paradise-crow Lycocorax obiensis is split from Halmahera Paradise-crow (formerly Paradise-crow) L. pyrrhopterus (Clements 2007:­­583)

Summary: The Obi Paradise-crow is now considered an endemic species to the central Moluccan island of Obi.

Details: The three recognized taxa of Lycocorax were all originally described as full species, but have long been considered conspecific (e.g., Mayr 1962). On Halmahera, Lycocorax pyrrhopterus is a shy, fairly quiet bird but on Obi it is much more demonstrative and vocal (Lambert 1994, Thibault et al. 2013), with some notably different call types. In addition, there are subtle plumage differences, including the curled eyebrows of obiensis that are not obviously so in pyrrhopterus. The taxon morotensis also shows some differences from pyrrhopterus, but these do not approach the same level of differentiation as does obiensis. del Hoyo and Collar (2016) and Eaton et al. (2016), followed by Gill et al. (2021, IOC v.11.2) split obiensis at the species level but retained morotensis as a subspecies of pyrrhopterus, and WGAC and Clements et al. (2023) now follow suit.

English names: TheEnglish names adopted here are the same as those used by del Hoyo and Collar (2016), Eaton et al. (2016), and Gill et al. (2021, IOC v.11.2).

Eastern Parotia Parotia helenae is split from Lawes’s Parotia Parotia lawesii (Clements 2007:584)

Summary: The north side of the mountains of southeastern New Guinea now have their own species of Parotia bird-of-paradise, the Eastern Parotia, which closely resembles the more widely distributed Lawes’s Parotia except in nasal feathering in both sexes.

Details: Parotia helenae was the only one of the taxa treated as a subspecies of P. lawesii in e.g., Mayr (1962) that was originally described as a full species. Its conspecificity as espoused by Mayr (1962) has not been widely accepted, however, as Schodde and McKean (1973) showed that it is parapatric or possibly locally sympatric, with no known intergrades. Genetically P. helenae is fairly close to P. lawesii (Irestedt et al. 2009) and it is also similar in its display characteristics (Scholes 2008), but the consistent morphological differences in the face of parapatry led WGAC followed by Clements et al. (2023) to agree with those sources that consider helenae a distinct species, including Beehler and Pratt (2016), Gregory (2017), and Gill and Wright (2006, IOC v.1.0).

English names: The English names Eastern Parotia for P. helenae and Lawes’s Parotia for P. lawesii have a long history of usage (e.g., Gill and Wright 2006, IOC v.1.0) and are adopted here.

Palawan Crow Corvus pusillus is split from Slender-billed Crow Corvus enca (Clements 2007:­­593)

Summary: The Palawan Crow is a common species that gives unmistakable deep raspy short croaks, limited to the Palawan island group and Mindoro island of the southwestern Philippines.

Details: Corvus pusillus, like most of the taxa comprising the Corvus enca complex (e.g., Blake and Vaurie 1962), was originally described as a full species. Rand and Rabor (1961) reviewed the morphology of the disparate Philippine forms, each of them rare and little-known except the common pusillus. They indicated that Palawan and Mindoro pusillus has the grayest sheen of the Philippine forms and the whitest feather bases, while also being generally lankier than the others (Rand and Rabor 1961). Vocal differences have long been known (e.g., Dickinson et al. 1991). Boesman (2016 [No. 428]) found four main vocal groups within C. enca but did not consider the Palawan Crow Corvus pusillus the most distinctive. Allen (2020) limbo-split pusillus and gave concise vocal descriptions, and numerous recordings now available clearly indicate the great vocal distinctiveness of pusillus, which gives mostly short, upturned, but very deep and froglike rasps. Clements et al. (2023) and Gill et al. (2021, IOC v.11.2) now agree in treating pusillus as a full species. The vocal and size-related distinctiveness of sierramadrensis Luzon and samarensis of Samar and at least formerly Mindanao indicate that further changes to species limits of the Philippine members of Corvus enca will be necessary, and within Indonesia, Eaton et al. (2016) have enacted splits of the Bornean compilator and the Sulawesi region celebensis groups. This set of issues has not yet been considered by WGAC.

English names: The apt namePalawan Crow as used in del Hoyo et al. (2016), Allen (2020), and Gill et al. (2021, IOC v.11.2) is adopted here.

Cuban Palm-Crow Corvus minutus is split from Hispaniolan Palm- (formerly Palm) Crow Corvus palmarum (Clements 2007:­­594)

Summary: Cuban and Hispaniolan Palm-Crows are now endemic to those islands, the Cuban to a small, mainly palm savanna area of central Cuba and the Hispaniolan mainly to pine and drier forests of that island.

Details: First described as a separate species and maintained as such at least until 1904 (Ridgway 1904), Corvus minutus of Cuba has usually been considered conspecific with C. palmarum of Hispaniola (e.g., Blake and Vaurie 1962), or even indistinguishable (Johnston 1961). Garrido et al. (1997) however presented sonagrams and maintained they should be treated as separate species, which received a limited following; in fact, Gill and Wright (2006, IOC v.1.0) and the Clements checklists treated them as two species until 2011. Boesman (2016 [No. 209]) quantified vocal differences as a score of 3 (fairly high), but del Hoyo and Collar (2016) stated that the vocal differences are minor. Many recordings of each are now available and they are quite consistently different. In addition, genetic analysis shows them to be sister taxa with a depth of divergence similar to some other crow species pairs (Jønsson et al. 2012); they have been said to have different egg coloration (in Kirwan et al. 2019), and they appear to differ in behavior when calling (summarized in https://americanornithology.org/wp-content/uploads/2023/08/2023-B.pdf). Further study is needed but WGAC and Clements et al. (2023) agree with NACC (Chesser et al. 2023) and Gill and Wright (2006, IOC v.1.0) in considering C. minutus a separate species.

English names: The English names follow those widely used in previous sources and are reasonably apt, especially for the Cuban species, although C. palmarum of Hispaniola now primarily occurs in pine forest.

Spotted Berrypecker Melanocharis piperata is split from Thick-billed (formerly Spotted) Berrypecker M. crassirostris (Clements 2007:544)

Summary: In the eastern mountains of New Guinea, the Spotted Berrypecker replaces the Thick-billed Berrypecker of the western mountains. Males look similar except for the bill, while females differ strikingly.

Details: Melanocharis piperata of eastern New Guinean mountains was originally described as a full species but has long been united with M. crassirostris of the island’s western mountains (e.g., Salomonsen 1967). The bill length and coloration differ markedly, as does female plumage, and there is no evidence of intergradation despite close approach. They are thus recognized as separate species in Beehler and Pratt (2016) as well as del Hoyo and Collar (2016) and Gill et al. (2021, IOC v.11.2), and now WGAC and Clements et al. (2023) follow suit.

English names: The names adopted here align with those of Beehler and Pratt (2016), del Hoyo and Collar (2016), and Gill et al. (2021, IOC v.11.2).

Black-capped Robin Heteromyias armiti issplit from Ashy (now Arfak) Robin H. albispecularis (Clements 2007:­­482)

Summary: Arfak Robin is endemic to the mountains of the Vogelkop Peninsula of northwestern New Guinea, while Black-capped Robin is found in the mountains of the mainland of New Guinea.

Details: Of the five taxa long considered subspecies of Heteromyias albispecularis (Mayr 1986), only H. armiti was described as a full species, but the others were described only between 1930 and 1940, by which time Hartert (1930) agreed with Stresemann that armiti and subspecies of mainland New Guinea should be treated as conspecific with albispecularis of the West Papuan peninsula, despite its head markings that “give it a rather different appearance”. Thus H. albispecularis has long been treated as polytypic and widespread, until Pratt and Beehler (2015) considered them separate species based on plumage, song, and DNA divergence; the split was also adopted by del Hoyo and Collar (2016), followed by Gill et al. (2021, IOC v.11.2). This change was based not only on the obvious plumage differences but also differences in song (Pratt and Beehler 2015, Boesman 2016 [No. 215]). There is also an undescribed population in the Foja Mountains of northwestern New Guinea whose affinities are unclear. Based on the distinct plumage and song, WGAC and Clements et al. (2023) join previous authors in considering albispecularis and armiti distinct species. In addition, Beehler and Pratt (2016) subsume the subspecies centralis in rothschildi (a subspecies of armiti) and the subspecies atricapilla in nominate armiti, but Clements et al. (2023) tentatively retain both as do del Hoyo and Collar (2016) and Gregory (2017).

English names: Because Ashy Robin has long been used to refer to the combined species, Clements et al. (2023) adopt the geographically apt name Arfak Robin for H. albispecularis, retaining Black-capped Robin as used in Pratt and Beehler (2015) and del Hoyo and Collar (2016) for H. armiti.

Madagascar Martin Riparia cowani is split from Plain Martin R. paludicola (Clements 2007: 358)

Summary: The amazingly endemic-rich island of Madagascar now has yet another endemic, the Madagascar Martin, split from the widespread African Plain Martin.

Details: As with several of the taxa long treated as subspecies of Riparia paludicola (Mayr and Greenway 1960a), Riparia cowani was originally described as a full species, though by 1937 (Bannerman 1937) a version of the modern polytypic species of R. paludicola was recognized. del Hoyo and Collar (2016), on the basis of plumage distinctions and the “very different vocalizations” (Boesman 2016 [No. 412]) of R. cowani, considered cowani a separate species. Brown (2019), in an unpublished Ph.D. study using UCE data, found a relatively deep divergence between R. cowani and R. paludicola, deeper than other subspecies in the study. Thus, WGAC and Clements et al. (2023) agree with del Hoyo and Collar (2016) in treating R. cowani as specifically distinct.

English names: The widely distributed Plain Martin R. paludicola retains its English name. We follow del Hoyo and Collar (2016) in using Madagascar Martin for R. cowani; the Mascarene Martin Phedina borbonica has a considerably broader distribution including the region’s islands, and that name is long-entrenched.

Siberian House-Martin Delichon lagopodum is split from Western (formerly Common) House-Martin D. urbicum (Clements 2007:361)

Summary: The house-martin of northeastern and north-central Asia is now a distinct species known as Siberian House-Martin. In parts of Siberia and Mongolia it overlaps with the sympatric Western House-Martin, and in southern parts of its breeding range and in winter from Asian House-Martin; it can usually be identified from both by its more extensively white rump.

Details: Delichon lagopodum of northeastern Asia was originally described as a full species, though it soon was included within an expansive D. urbicum species (Hartert 1910). Since that time, it has been shown that D. dasypus is sympatric and cannot be conspecific, but confusion has long reigned with respect to the status of D. lagopodum. del Hoyo and Collar (2016) treated lagopodum as a separate species based on plumage and morphometric differences as well as apparent parapatry, but Shirihai and Svensson (2018) stated local overlap was suspected and that it required study. Now, it has been conclusively shown to be sympatric with D. urbicum in southeastern Siberia and Mongolia (Leader et al. 2021), and in addition it is readily identified in the field, has somewhat distinct vocalizations (Leader et al. 2021, https://americanornithology.org/wp-content/uploads/2023/08/2023-B.pdf), and seems to be paraphyletic with urbicum (instead being sister to D. dasypus) in an unpublished UCE phylogeny (Brown 2019). WGAC and Clements et al. (2023) thus join del Hoyo and Collar (2016), NACC (Chesser et al. 2023), and Gill et al. (2021, IOC v.11.2) in according species status to D. lagopodum.

English names: The English names adopted align with those of Chesser et al. (2023), and Gill et al. (2021, IOC v.11.2), which we consider clearer and more apt than those used by del Hoyo and Collar (2016).

Sumatran Bulbul Ixos sumatranus is split from Sunda (now Javan) Bulbul I. virescens(Clements 2007:384)

Summary: Sumatra and Java each now have another endemic species, the Sumatran and Javan Bulbuls.

Details: Ixos sumatranus of Sumatra was first described as a separate species from I. virescens of Sumatra, but even then it was then stated to be “a representative of H. virescens” (Wardlaw Ramsay 1882). It was long treated as a subspecies of I. virescens (e.g., Mayr and Greenway 1960b), but Gill and Donsker (2012; IOC v.3.1) considered them separate species, as did del Hoyo and Collar (2016), on the basis of plumage and vocal differences (the latter from a small sample; Boesman 2016 [No. 243]) and Eaton et al. (2016) also split sumatranus from virescens. Based on this, WGAC and Clements et al. (2023) join the above authors in recognizing I. sumatranus as a full species.

English names: The geographical English names adopted for these two are apt and familiar through use in previously listed sources.

Banggai Golden-Bulbul Hypsipetes harterti is split from Sula Golden-Bulbul H. longirostris(Clements 2007:383)

Summary: The Banggai Golden-Bulbul is yet another newly recognized endemic species to the long-overlooked Banggai Islands east of Sulawesi.

Details: Most forms long considered conspecific as Golden Bulbul Hypsipetes affinis (Mayr and Greenway 1960b) were originally described as separate species. The exception is harterti of the Banggai Islands, first considered the same as the Sula form H. longirostris and then described as a subspecies of the Seram form, H. affinis (Stresemann 1912), which suggests that Stresemann was already considering all the golden bulbuls conspecific by 1912. Most taxa in the H. affinis complex have more recently been accorded species status by e.g., Collar et al. (2013), with H. harterti finally being recognized as specifically distinct by Eaton et al. (2016) and del Hoyo and Collar (2016) on the basis of morphology and vocal differences (e.g., Boesman 2016 [No. 426]). WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.2).

English names: The geographic and group name Banggai Golden-Bulbul is apt and uses names already well-established through use by Eaton et al. (2016) and del Hoyo and Collar (2016).

Camiguin Bulbul Hypsipetes catarmanensis is split from Yellowish Bulbul H. everetti (Clements 2007:­­384)

Summary: The tiny island of Camiguin, within sight of Mindanao, now has its own distinct species of bulbul.

Details: Hypsipetes catarmanensis of Camiguin Island, just north of Mindanao, was not described until 1969 (Rand and Rabor 1969) and was then considered a subspecies of H. everetti, but its larger size and plumage differences from the other H. everetti taxa were noted. Its vocalizations have also been qualitatively considered to differ (Kennedy et al. 2000), and a genetic divergence of 3.4% was found by Oliveros et al. (2010). The Sulu Islands form H. [e.] haynaldi is also divergent in plumage, and both were split by del Hoyo and Collar (2016) and Allen (2020), but WGAC, Gill et al. (2021, IOC v.11.2), and Clements et al. (2023) considered the evidence for specific status for haynaldi weaker than that of H. catarmanensis, and thus WGAC and Clements et al. (2023) consider H. catarmanensis a distinct species, while continuing to treat haynaldi as a race of everetti. However, many more recordings of haynaldi have recently become publicly available, and its status could now be reevaluated with more confidence.

English names: The geographically appropriate English name adopted for Camiguin Bulbul H. catarmanensis aligns with that used in del Hoyo and Collar (2016), Allen (2020), and Gill et al. (2021, IOC v.11.2), while that of the more widespread H. everetti,including the Sulu form haynaldi remains the more familiar name Yellowish Bulbul.

Pale-eyed Bulbul Pycnonotus davisoni is split from Stripe-throated Bulbul P. finlaysoni (Clements 2007:378)

Summary: The woodlands of the Ayeyarwady (Irrawaddy, southern Myanmar) delta region are home to the quiet, unobtrusive Pale-eyed Bulbul.

Details: Pycnonotus davisoni was originally described as a species, with the statement that it was clearly allied to P. finlaysoni but still quite distinct (Hume 1875), and it was treated as a species by some at least until 1896 (Büttikofer 1896) but for many years its status as a subspecies was uncontested (e.g., Mayr and Greenway 1960b). There is however a striking difference in iris color between davisoni and finlaysoni, and evidence of sympatry. del Hoyo and Collar (2016) considered P. davisoni to be a full species, and WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.2) agree in enacting this treatment.

English names: Clements et al. (2023) adopts the English names used by del Hoyo and Collar (2016).

Pale-faced Bulbul Pycnonotus leucops is split from Flavescent Bulbul P. flavescens (Clements 2007:378)

Summary: The unmistakable Pale-faced Bulbul is now yet another endemic species to the endemic-rich mountains of northeastern Borneo.

Details: The highly disjunct and distinctive Pycnonotus leucops of montane northeastern Borneo was originally named a separate species from P. flavescens, and a new genus was erected for it (Sharpe 1888), while the other two (weakly marked) subspecies of flavescens were described later as subspecies. However, leucops has long been considered a subspecies of flavescens (e.g., Mayr and Greenway 1960b). Genetic data suggest it is not particularly closely related to flavescens, and that the two are not even sister taxa (Dejtarodol 2016). There seem to be vocal differences as well (Boesman 2016 [No. 245]) but larger samples are needed. del Hoyo and Collar (2016) and Eaton et al. (2016), followed by Gill et al. (2021, IOC v.11.2), treated leucops as a separate species, and WGAC and Clements et al. (2023) agree that P. leucops should not continue to be treated as a subspecies.

English names: The apt descriptive name Pale-faced Bulbul for P. leucops has become familiar through use in del Hoyo and Collar (2016) and Eaton et al. (2016), and is adopted here. The widely distributed Flavescent Bulbul retains its existing name.

Eye-ringed Parrotbill Suthora ricketti is split from Brown-winged Parrotbill S. brunnea (Clements 2007:512)

Summary: China now has another endemic species, the Eye-ringed Parrotbill of Sichuan and Yunnan.

Details: Though originally described as a subspecies of S. webbiana, S. ricketti was nevertheless recognized as a full species as late as 1964 by Deignan (1964). Still, most recent treatments have considered ricketti a subspecies of webbiana (e.g., Wolters 1980) or of brunnea (Clements 2007, Dickinson and Christidis 2014). del Hoyo and Collar (2016) treated S. ricketti as a full species on the basis of morphology, genetic distance, and vocalizations (Wright et al. 2014). A recent DNA phylogeny (Dai and Feng 2023) found rather deep genetic divergence between brunnea and ricketti in apparent parapatry, leading WGAC and Clements et al. (2023) to subscribe to this split.

English names: Although “Yunnan Parrotbill” has been used extensively for S. ricketti, that name is somewhat misleading as its range is largely in Sichuan, while Brown-winged S. brunnea sensu stricto occurs primarily in Yunnan. Hence we have selected a descriptive name that highlights one of the most distinctive features of S. ricketti.

Calabarzon Babbler Sterrhoptilus affinis is split from Black-crowned (now Visayan) Babbler S. nigrocapitatus (Clements 2007:500)

Summary: The Calabarzon Babbler is now another Luzon endemic, found mainly in the southeastern part of the island, while Visayan Babbler is found only in the east-central Philippines.

Details: Four of the five taxa long recognized as subspecies of S. capitalis (e.g.,Deignan 1964) were originally described as species, and they were still recognized as such by McGregor (1909). A three-species treatment was however adopted in Dickinson et al. (1991), and this has largely been followed since. The mtDNA phylogeny of Hosner et al. (2018) suggests paraphyly that would require either treatment as four species or a single species. This, coupled with the plumage divergence involved led WGAC and Clements et al. (2023) to agree with Gill et al. (2021, IOC v.11.2) in considering S. affinis a full species. Vocalizations are not well known or studied in the group, and further media and study are needed.

English names: The English names adopted align with Gill et al. (2021, IOC v.11.2). “Calabarzon” refers to part of the geographic range of S. affinis, now primarily found in southeastern Luzon, while Visayan Babbler is adopted for S. nigrocapitatus s.s. of Samar, Leyte, and Bohol, the East Visayas of the east-central Philippines.

Morotai White-eye Zosterops dehaani is split from Cream-throated White-eye Z. atriceps (Clements 2007:553)

Summary: The Morotai White-eye is a newly recognized endemic species to the northern Moluccan island of Morotai, in eastern Indonesia.

Details: The three taxa long recognized as subspecies of Z. atriceps (Mayr 1967) were all originally described as separate species. Eaton et al. (2016) once again considered all four to be separate species based on plumage and vocal differences, which were examined in greater detail by Rheindt and Eaton (2018). Of all the taxa (a fourth remaining undescribed from Obi), the Morotai taxon dehaani is much the most distinct both in plumage and vocally, and Gill and Donsker (2019; IOC v.9.2) adopted this split, as now have WGAC and Clements et al. (2023). Further evidence would be needed to accord the same status to the Halmahera subspecies fuscifrons.

English names: The name of the island to which it is endemic is adopted for the Morotai White-eye Z. dehaani, while the long-standing name Cream-throated White-eye is retained for the more widespread Z. atriceps s.s.

Bougainville White-eye Zosterops hamlini andGuadalcanal White-eye Z. oblitus are split from Gray-throated White-eye Z. rendovae (Clements 2007:554)

Summary: The Solomon Islands now have three more endemic species of montane white-eye, the Bougainville, Guadalcanal, and Gray-throated white-eyes (the latter restricted to Makira, southeastern Solomon Islands).

Details: Zosterops hamlini and Z. oblitus were originally described as subspecies of a Solomons species with an extraordinarily complex and confusing nomenclatural history, beyond the scope of this review. They were long (e.g., Mayr 1967) treated as conspecific with Z. rendovae (but as Z. ugiensis, now treated as pertaining to a different species group). The widely disjunct Bougainville form hamlini was suggested by the mostly mtDNA phylogeny of Moyle et al. (2009) to be only distantly related to rendovae, and it is strikingly different in plumage and vocalizations, leading del Hoyo and Collar (2016) to split them. The case of Z. oblitus of Guadalcanal is less clear-cut, but the genomic data of Manthey et al. (2020) lend strong support to its split, and both are now adopted by WGAC, Gill et al. (2021, IOC v.11.2), and Clements et al. (2023).

English names: The newly split Bougainville and Guadalcanal white-eyes take their names from their islands of endemism, and the former was also used by del Hoyo and Collar (2023). The English name of Gray-throated White-eye for Z. rendovae, now limited to Makira, may be reconsidered.

Malayan Black-capped Babbler Pellorneum nigrocapitatum andBornean Black-capped Babbler P. capistratoides are split from Javan Black-capped (formerly Black-capped) Babbler P. capistratum (Clements 2007:494)

Summary: There are now three species of “Black-capped Babbler”: Malayan, Bornean, and Javan Black-capped Babbler, each in different parts of the Sundaic region.

Details: Three of five taxa long treated as subspecies of Pellorneum capistratum (e.g., Deignan 1964) were originally described as full species. del Hoyo and Collar (2016) considered only nigrocapitatum (of Borneo and Sumatra) to be specifically distinct from Javan capistratum, and Eaton et al. (2016) suggested there may be four species, though Eaton et al. (2021) enacted a three-species treatment, followed by Gill et al. (2021, IOC v.11.2).These three have now been conclusively shown to require treatment as full species on the basis of genomic analyses (Garg et al. 2022), as well as differences in vocalizations (though deemed rather minor by Boesman 2016 [No. 269]).

English names: The English names adopted follow Eaton et al. (2021) in using geographic descriptors along with the group name “Black-capped” for clarity and familiarity.

Tanzanian Illadopsis Illadopsis distans is split from Pale-breasted Illadopsis I. rufipennis (Clements 2007:495)

Summary: Tanzania now has an endemic species of illadopsis, the Tanzanian Illadopsis, found mostly in the northeast.

Details: Originally described as a subspecies of Illadopsis rufipennis and treated as thus ever since (Deignan 1964), I. distans was however noted by Zimmerman et al. (1996) and Stevenson and Fanshawe (2002) to have a very distinctive voice. It was split by del Hoyo and Collar (2016) on the basis of its very different song (Boesman 2016), supplemented by minor morphological distinctions and biogeography, and this is now agreed upon by WGAC, Clements et al. (2023), and Gill et al. (2021, IOC v11.2). In addition, the subspecies puguensis is synonymized with distans due to lack of known differences (Collar and Robson 2007).

English names: The geographic name Tanzanian Illadopsis also used by Gill et al. (2021, IOC v11.2) is adopted here because this species is the only illadopsis widely distributed in and endemic to Tanzania, and thus it is deemed a more helpful name than the name Grey-breasted Illadopsis was used for I. distans by del Hoyo and Collar (2016). The long-established name Pale-breasted Illadopsis is retained by the widely distributed I. rufipennis s.s.

Siberian Nuthatch Sitta arctica is split from Eurasian Nuthatch S. europaea (Clements 2007:529–530)

Summary: Eastern Russia now has its own endemic species of nuthatch, the Siberian Nuthatch. This species may co-occur with local forms of Eurasian Nuthatch and they may even flock together in the non-breeding season.

Details: Just one of several taxa originally described as full species that have long been united in Sitta europaea (e.g., Greenway 1967), S. arctica was not even described to science until 1907. Although it has numerous differences in details of plumage and proportions, these are not visually striking when compared with the vast variation exhibited by the S. europaea complex. However, Sitta arctica was found to be highly distinct in an mtDNA study (Zink et al. 2006), so much so that it was used to root the trees of S. europaea in Hung et al. (2012). It is evidently sympatric with S. europaea, and said to have very different vocalizations (Red’kin and Konavalova 2006). It was thus split by several sources including Dickinson and Christidis (2014) and del Hoyo and Collar (2016), and followed by Gill and Wright (2008, IOC v.1.6), and now WGAC and Clements et al. (2023). A recent multi-locus phylogeny (Päckert et al. 2020) confirms that S. arctica is basal to the large clade comprising most of the Asian Sitta species, and thus species status is unequivocally upheld.

English names: The name Siberian Nuthatch used by del Hoyo and Collar (2016) and Gill and Wright (2008, IOC v.1.6) is adopted here, although the name Taiga Nuthatch used by Dickinson and Christidis (2014) would also be appropriate if less geographically indicative.

Flame-crowned Flowerpecker Dicaeum kampalili is split from Yellow-crowned (formerly Flame-crowned) Flowerpecker D. anthonyi (Clements 2007:546)

Summary: The mountains of Luzon and Mindanao now each have endemic flowerpecker species, the Flame-crowned only in Mindanao and the Yellow-crowned in Luzon.

Details: The first-named Mindanao taxon of the complex, until recently treated as subspecies of Dicaeum anthonyi (e.g., Salomonsen 1967), was described as a full species, albeit with a name change to D. kampalili later that year (Manuel and Gilliard 1953) due to preoccupation. A few years later, the taxon masawan was described from the Zamboanga Peninsula of western Mindanao, with the statement that it “bridges part of the difference” between Luzon anthonyi and Mindanao kampalili (Rand and Rabor 1957), but it is much closer to kampalili than anthonyi and is not found in an intervening area between those two. Although genetic and adequate vocal samples are as yet unavailable, D. kampalili (including masawan) were considered separate species by del Hoyo and Collar (2016), followed by Gill et al. (2021, IOC v.11.2). WGAC and Clements et al. (2023) agree that the morphological differences and biogeography better align with species than subspecies status in this group.

English names: As with del Hoyo and Collar (2016) and Gill et al. (2023), the long-standing name Flame-crowned Flowerpecker is retained for the more widespread Mindanao species D. kampalili, while the apt name Yellow-crowned Flowerpecker is adopted for the Luzon species Dicaeum anthonyi s.s.

Cambodian Flowerpecker Dicaeum cambodianum, Fire-throated Flowerpecker D. luzoniense, andSumatran Flowerpecker D. beccarii are split from Fire-breasted Flowerpecker D. ignipectus (Clements 2007:548)

Summary: Four species now result from reexamination of the Fire-breasted Flowerpecker complex: Cambodian Flowerpecker of southeastern Thailand and Cambodia; Fire-throated Flowerpecker of the Philippines; Sumatran Flowerpecker of the mountains of Sumatra; and Fire-breasted Flowerpecker, widespread in continental southern Asia.

Details: Several taxa long united as Dicaeum ignipectus (Salomonsen 1967) were initially described as separate species, and of these arguably the most visually distinctive, D. cambodianum, which ismainly found in Cambodia, was first considered a subspecies of D. beccarii of Sumatra (Delacour and Jabouille 1928). Boesman (2016 [No. 409]) found evidence for four vocal groups, although further samples and analysis is needed. These groups correspond to geographical taxon groups, and del Hoyo and Collar (2016) treated these as the four species listed above. Eaton et al. (2021) considered Sumatran beccarii a separate species but did not comment on the non-Indonesian taxa. Dicaeum cambodianum, in addition to seemingly lacking a common song type of D. ignipectus, also appears to be parapatric with D. ignipectus. WGAC and Clements et al. (2023) hence agree that the four-species treatment is preferable.

English names: The English names used by del Hoyo and Collar (2016) are adopted as apt; in particular, the name Fire-throated Flowerpecker for the Philippine bird emphasizes an important difference between it and D. ignipectus.

Pink-breasted Flowerpecker Dicaeum keiense is split from Mistletoebird Dicaeum hirundinaceum (Clements 2007:548)

Summary: The Kei Islands and Tanimbar of the far eastern Indonesian archipelago now have an endemic flowerpecker species, named Pink-breasted Flowerpecker for its unique coloration.

Details: All four recognized taxa long considered subspecies in the Dicaeum hirundinaceum complex (Salomonsen 1967) were originally described as full species. del Hoyo and Collar (2016) split the complex into three species: keiense of Kai and nearby islands with fulgidum of the Tanimbar Islands; ignicolle of the Aru Islands; and hirundinaceum of Australia.

On the basis of morphological differences, Clements et al. (2023) split Dicaeum keiense (temporarily including D. ignicolle; ignicolle Gray, GR, 1858 would have priority over keiense          Salvadori, 1874 but this treatment is unlikely to hold in future updates) from D. hirundinaceum. The taxonomic status of Aru Islands ignicolle requires further study but WGAC now considers it a subspecies of D. hirundinaceum.

 English names: The name Pink-breasted Flowerpecker used for D. keiense by del Hoyo and Collar (2016) is adopted here.

Ornate Sunbird Cinnyris ornatus, Sahul Sunbird Cinnyris frenatus, Tukangbesi Sunbird C. infrenatus, Palawan Sunbird C. aurora, South Moluccan Sunbird C. clementiae, Flores Sea Sunbird C. teysmanni, and Mamberamo Sunbird C. idenburgi are split from Garden Sunbird (formerly Olive-backed Sunbird) C. jugularis (Clements 2007:540–541)

Summary: Generally among the most common birds from southeast Asia through northern Australia, birders now can now see eight different species of “Olive-backed Sunbird”. One of these, the Mamberamo Sunbird of northern New Guinea, is little-known but may overlap with the widespread Sahul Sunbird; otherwise, the species do not co-occur, so identification is straightforward. However, several are limited to far-flung Indonesian island groups and thus seen by few birders.

Details: No fewer than fifteen of the 23 subspecies long recognized as comprising the C. jugularis complex (Rand 1967) were first described as separate species. Nevertheless, there has been surprisingly little effort toward revising this highly polytypic assemblage until recently. Lohman et al. (2010) showed remarkably deep divergences in mtDNA between taxa from different major geographic regions, and Marcaigh et al. (2022) further elucidated the picture of mtDNA divergence among Sulawesi region taxa. Vocalizations are complex but some differences between taxa in song are apparent. Beehler and Pratt (2015) and del Hoyo and Collar (2016) considered the little-known C. idenburgi of the inland lowlands of northern New Guinea to be a separate species largely due to apparent parapatry and possible sympatry. WGAC and Clements et al. (2023) consider that, on the basis of the deep mtDNA divergences, coupled with plumage and vocalizations, it is untenable to continue to treat the complex as a single species, and although crucial data other than plumages are lacking for some key taxa, eight species are now recognized.

English names: Most of the English names adopted are geographic descriptors, with the exception of southeast Asian and Sundaic Ornate Sunbird, which reflects the specific epithet, and Garden Sunbird of the Philippines, which is apt as the species is very common in gardens. They are also for the most part the names used as groups by del Hoyo and Collar (2016) and Eaton et al. (2016).

Palawan Fairy-bluebird Irena tweeddalii is split from Asian Fairy-bluebird Irena puella (Clements 2007:569)

Summary: The forests of the Palawan island group of the southwestern Philippines are the sole home of the Palawan Fairy-bluebird.

Details: All five taxa long recognized as subspecies of Irena puella (e.g., Mayr and Greenway 1960c) were originally described as separate species, although all are generally similar in their striking plumage pattern, which is unique to this complex. On the basis of mtDNA and nuclear DNA, Moltesen et al. (2012) and Lim et al. (2020) found that the Palawan form tweeddalii was sister to all other taxa of Irena puella. In addition to this evidence, del Hoyo and Collar (2016) enumerated multiple morphological differences that led them to consider I. tweeddalii as a distinct species, as did Eaton et al. (2016), Allen (2020), and Gill et al. (2021, IOC v.11.2). The few available recordings of tweeddalii suggest vocal differences. WGAC and Clements et al. (2023) consider that the evidence favors the treatment of tweeddalii as a full species.

English names: The names used by del Hoyo and Collar (2016) and others, Palawan Fairy-bluebird and Asian Fairy-bluebird, are apt and thus adopted here.

Blue-winged Leafbird Chloropsis moluccensis is split from Javan (formerly Blue-winged) Leafbird C. cochinchinensis (Clements 2007:386)

Summary: Java now has its own endemic species of leafbird, the Javan Leafbird, though it is becoming rare due to the cage-bird trade.

Details: Several of the taxa long treated as subspecies of Chloropsis cochinchinensis (Mayr and Greenway 1960c) were originally named as full species, but one with an especially complicated nomenclatural history is the nominate, much earlier and now again recognized to have been named from Java rather than Cochinchina (Wells et al. 2003). Males of nominate Chloropsis cochinchinensis differ conspicuously from other taxa still treated as conspecific (the moluccensis complex, which excludes C. jerdoni of Peninsular India and Sri Lanka and C. kinabaluensis of northeastern Borneo) in coloration of crown and wing, and were found to be more deeply diverged in mtDNA and nuclear DNA than the taxa in the moluccensis complex (Moltesen et al. 2012). Thus del Hoyo and Collar (2016) and Eaton et al. (2016), followed by Gill et al. (2021, IOC v.11.2), considered C. moluccensis a separate polytypic species from the monotypic Javan C. cochinchinensis, a position with which WGAC and Clements et al. (2023) now align.

English names: The sources listed above adopted the English names Blue-winged Leafbird for the widespread C. moluccensis, which aptly describes a shared plumage aspect, and Javan Leafbird for the narrowly endemic C. cochinchinensis.

Azores Chaffinch Fringilla moreletti, Madeira Chaffinch F. maderensis, Canary Islands Chaffinch F. canariensis, andAfrican Chaffinch F. spodiogenys are split from Common Chaffinch Fringilla coelebs (Clements 2007:625626)

Summary: The Azores Chaffinch, Madeira Chaffinch, Canary Islands Chaffinch, and African Chaffinch are each now species separate from the Common Chaffinch of continental Europe and western Asia.

Details: While all European forms (except the nominate) long treated as conspecific under Fringilla coelebs (Mayr 1968) were originally described as subspecies, all taxa from Macaronesian islands and northern Africa were described as full species. The complex has long been recognized for its marked polytypy and has been well-studied (summarized in Illera et al. 2016), including the considerable vocal disparity which however is of unclear significance for species limits in this complex due to vocal learning (e.g., Lachlan et al. 2013). Illera et al. (2016) proposed considering the taxa of each of the three main Macaronesian island groups as separate species, but this has not been widely followed. Shirihai and Svensson (2018) concluded based on unexpected results in early genetic analyses that all should be considered conspecific. However, the integrative taxonomic analysis of Recuerda et al. (2021) provided a solid framework in terms of morphological and genetic analysis that WGAC, Gill et al. (2023, IOC v.13.2), and Clements et al. (2023) agree strongly supports the recognition of five species, with the African forms being the weakest species candidate, despite the most obvious plumage differences.

English names: The English names adopted are apt geographic descriptors for the newly split species, while the long-used name Common Chaffinch is retained for the widely distributed nominate group.

Puerto Rican Euphonia Chlorophonia sclateri andLesser Antillean Euphonia C. flavifrons are split from Hispaniolan (formerly Antillean) Euphonia C. musica (Clements 2007:627)

Summary: The Caribbean avifauna increases by two attractively plumaged species with the recognition that Puerto Rican Euphonia and Lesser Antillean Euphonia are distinct species from Hispaniolan Euphonia.

Details: The Chlorophonia musica complex (sensu Storer 1970) comprised nine subspecies of which, due to earlier taxonomic changes, only three now remain in the Antillean complex C. musica. These three, the Puerto Rican C. sclateri, Hispaniolan C. musica, and the Lesser Antillean C. flavifrons, were all originally described as separate species, and male plumages differ markedly. del Hoyo and Collar (2016) considered each of these separate species on the basis of morphology. However, no genetic comparisons appear to have been made for these three, and vocalizations are at least broadly similar so far as known (Mason et al. 2022, https://americanornithology.org/wp-content/uploads/2023/08/2023-B.pdf). Nevertheless, WGAC, NACC (Chesser et al. 2023), Gill et al. (2023, IOC v.13.2), and Clements et al. (2023) align with del Hoyo and Collar (2016) in now considering each of these taxa separate species based on their morphological differences that are equivalent to or exceed those exhibited by other euphonia species.

English names: The geographical names adopted are those used by del Hoyo and Collar (2016).

Yellow-lored Tanager Chlorothraupis frenata is split from Carmiol’s Tanager Chlorothraupis carmioli (Clements 2007:652)

Summary: The Yellow-lored Tanager of the eastern Andes from southern Colombia to Bolivia is drably plumaged but easily distinguished from its former conspecific Carmiol’s Tanager mainly of Central America by locality and voice.

Details: Chlorothraupis frenata was originally described as a subspecies of C. carmioli, although it is separated geographically from the nearest population of carmioli (in extreme northern Colombia) by the more distinctively plumaged Chlorothraupis olivacea, and frenata has long been treated as a subspecies (Storer 1970). del Hoyo and Collar (2016) considered it a separate species based largely on vocal differences, as noted earlier by Ridgely and Greenfield (2001), followed by Hilty (2021) and Gill and Wright (2006, IOC v.1.0). Now, genomic data (Scott 2022) place frenata as sister to olivacea instead of to carmioli, further strengthening the case that carmioli as long recognized cannot be upheld. NACC (Chesser et al. 2023), SACC (https://www.museum.lsu.edu/~Remsen/SACCprop950.htm), WGAC, and Clements et al. (2023) now align in treating C. frenata as an independent species.

English names: The names used by del Hoyo and Collar (2016), Hilty (2021), and NACC (Chesser et al. 2023) are followed. The confusing and uninformative name Olive Tanager was used by Ridgely and Greenfield (2001) and Gill and Wright (2006, IOC v.1.0).

Ecuadorian Seedeater Amaurospiza aequatorialis is split from Blue Seedeater Amaurospiza concolor (Clements 2007:672)

Summary: The distribution of the Blue Seedeater is now limited to Middle America, while the scarce Ecuadorian Seedeater is found mainly in western Ecuador; it barely reaches southern Colombia and northern Peru.

Details: Each of the three taxa considered part of A. concolor in Paynter (1970) were originally described as a full species. However, the treatment of these widely disjunct taxa has varied since then. All are fairly similar in plumage and vocalizations. Recent molecular and integrative analyses (Scott 1922, Areta et al. 2023) support the treatment of A. aequatorialis as a separate species, while relicta is retained within A. concolor, the treatment now agreed upon by NACC (Chesser et al. 2023), WGAC, Gill and Donsker (2015; IOC v.5.2), and Clements et al. (2023); the SACC decision is pending.

English names: The English name Ecuadorian Seedeater aligns with Gill and Donsker (2015; IOC v.5.2) and Areta et al. (2023).

White-bellied Tanager Tangara brasiliensis is split from Turquoise Tanager Tangara mexicana (Clements 2007:659)

Summary: Southeastern Brazil now has yet another beautiful endemic species of tanager, the White-bellied Tanager.

Details: As with two other forms long treated as subspecies of Tangara mexicana (Storer 1970), T. brasiliensis was first described as a separate species but lumped following Zimmer (1943), who stated “I believe the relationship is sufficiently close to warrant the use of a trinomial, with the added advantage of indicating the affinity of mexicana and brasiliensis in distinction from the other members of the genus Tangara”. On the basis of marked plumage and size differences, coupled with moderate mtDNA divergence (Burns and Naoki 2004), Mallet-Rodriguez and Gonzaga (2015) and del Hoyo and Collar (2016) considered T. brasiliensis a separate species; and WGAC and Clements et al. (2023) now align with this treatment. Gill and Wright (2006, IOC v.1.0–1.6) treated T. brasiliensis as specifically distinct, but from IOC v.3.1–13.1 it was considered a subspecies, once again being treated as a species in Gill et al. (2023, IOC 13.2).

English names: The name White-bellied Tanager has been widely used in the above sources, and is adopted here as well, while maintaining the familiar Turquoise Tanager for the widespread T. mexicana.

Grand Cayman Bullfinch Melopyrrha taylori is split from Cuban Bullfinch Melopyrrha nigra (Clements 2007:672)

Summary: The Cayman Islands now have an endemic species, the scarce Grand Cayman Bullfinch; both it and the Cuban Bullfinch are declining species.

Details: Originally named as a separate species, Melopyrrha taylori of Grand Cayman Island has been treated as a subspecies of M. nigra of Cuba and its satellites (Bond 1940, Paynter 1970). However, its considerably larger size and differences in plumage and degree of sexual dimorphism, as well as putative differences in voice (Garrido et al. 2014) led to its split in del Hoyo and Collar (2016), and these differences (summarized in https://americanornithology.org/wp-content/uploads/2023/03/2023-A.pdf) are considered more aligned with species than subspecies status by NACC (Chesser et al. 2023) and WGAC, followed by Clements et al. (2023) and Gill et al. (2023, IOC v.13.2).

English names: The geographic name Grand Cayman Bullfinch, used by the above sources, is apt and adopted here, with Cuban Bullfinch being retained for the more widespread M. nigra as in those sources.

New Species

Principe Scops-Owl Otus bikegila is recognized as a species new to science

Summary: A mysterious scops-owl of Príncipe Island, Gulf of Guinea, West Africa has finally been described to science after intensive study confirming its distinctiveness.

Details: After many years of reports by locals and then birders, the Principe Scops-Owl Otus bikegila Melo et al., 2022 has finally been described to science as a single-island endemic to low-elevation old-growth forest of Príncipe (Melo et al. 2022). This new species has been shown to be highly distinct in vocalizations, morphology, and genetics, surprisingly so for a small island near the African continent. WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.1) now align on the recognition of O. bikegila.

English names: The specific epithet of the new species honors local ornithologist Ceciliano do Bom Jesus, known locally as ‘Bikegila’, who was instrumental in its discovery and description.

Wangi-Wangi White-eye Zosterops paruhbesar is recognized as a species new to science

Summary: The island of Wangi-wangi southeast of Sulawesi has a new species of white-eye, the Wangi-Wangi White-eye, first noted as distinctive two decades ago.

Details: First noted in 2002, a distinctive new species of white-eye Wangi-Wangi White-eye Zosterops paruhbesar Irham et al., 2022 has finally been described to science. It is found only on Wangi-wangi Island of the Wakatobi or Tukangbesi Archipelago off southeastern Sulawesi, and although somewhat adaptable in habitat requirements, is threatened by the cage bird trade (Irham et al. 2022). WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.1) now align on the recognition of Zosterops paruhbesar.

English names: Referred to in Clements et al. (2023) as Wangi-Wangi White-eye, the capitalization will be corrected to Wangi-wangi White-eye in future updates.

Ibera Seedeater Sporophila iberaensis is recognized as a species new to science

Summary: A new species of seedeater, the Ibera Seedeater, has been named from northern Argentina, and has now also been reported from some surrounding regions.

Details: A long-overlooked seedeater from northern Argentina has been validly named Sporophila iberaensis Di Giacomo and Kopuchian, 2016. A previously assigned name is not considered nomenclaturally valid. Considerable taxonomic and nomenclatural confusion remains to be clarified regarding this incipient species (Areta et al. 2016, Galluppi-Selich et al. 2018, Turbek et al. 2021; https://www.museum.lsu.edu/~Remsen/SACCprop715.htm). However, WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.2) now align on the recognition of Sporophila iberaensis, recognizing that there is a high probability of further nomenclatural adjustment in this case.

English names: The English name Ibera Seedeater refers to the important wetlands that are the main habitat of this range-restricted species.

Lumps

Green-backed Woodpecker Campethera cailliautii is lumped into Little Green (now Green-backed) Woodpecker C. maculosa (Clements 2007:248–249)

Summary: Two small woodpeckers that occur over much of Africa are now considered conspecific due to frequent hybridization over a wide area.

Details: Green-backed Woodpecker Campethera cailliautii and Little Green Woodpecker C. maculosa are two dissimilar-plumaged small African woodpeckers that have long been known to hybridize (Chapin 1952, Prigogine 1988). Their voices seem very similar, they are closely related (Fuchs et al. 2017a), and their subspecies have been variously allied in different treatments. WGAC and Clements et al. (2023) now consider them conspecific on the basis of currently available data, as Green-backed Woodpecker C. maculosa.

English names: The long-familiar and apt English name Green-backed Woodpecker is now adopted by Clements et al. (2023) for the entire complex.

Scale-breasted Woodpecker Celeus grammicus is lumped into Waved Woodpecker C. undatus (Clements 2007:256)

Summary: The Waved Woodpecker now includes the widely distributed and highly variable Scale-breasted Woodpecker, and its range now includes most of northern South America.

Details: The Scale-breasted Woodpecker Celeus grammicus of western and central Amazonia and Waved Woodpecker C. undatus of the Guianan Shield region have long been treated as two species and were not even placed consecutively in Peters (1948). Short (1972), however, questioned their treatment as two species. Recent analyses have shown them to be vocally and morphologically undiagnosable, as well as being phylogenetically intermixed in genetic analyses (Benz and Robbins 2011, Sampaio et al. 2018). Hence WGAC and Clements et al. (2023) now treat them as conspecific. A SACC proposal (https://www.museum.lsu.edu/~Remsen/SACCprop980.htm) is in progress.

English names: The English name adopted for the combined species is Waved Woodpecker, which echoes the specific epithet.

Tabar Pitta Erythropitta splendida and New Britain Pitta E. gazellae are lumped into New Ireland (now Bismarck) Pitta E. novaehibernicae (Clements 2007:267)

Summary: The Bismarck Pitta can be found on the main islands of the Bismarck Archipelago, and a strongly marked form occurs on small Tabar Island, east of New Ireland.

Details: The Bismarck Archipelago forms of the former Red-bellied Pitta Erythropitta erythrogaster complex form a discrete clade (Irestedt et al. 2013), and were united as such by Gill and Donsker (2016, IOC v.6.3). Though splendida of Tabar Island and gazellae of New Britain exhibit sufficient morphological differences to be deemed separate species under a 7-point system (Collar et al. 2015), they are deemed better considered conspecific given recency of divergence and general similarity by WGAC and Clements et al. (2023).

English names: The English name Bismarck Pitta is apt for this group of taxa when united as a species, and is already familiar with use by Gill and Donsker (2016, IOC v.6.3).

Sangihe Pitta Erythropitta caeruleitorques and Siau Pitta E. palliceps are lumped into Sulawesi Pitta E. celebensis (Clements 2007:267)

Summary: The islands of Sangihe and Siau now share their “Red-bellied Pitta” subspecies with Sulawesi.

Details: The Sulawesi region taxa of the former Red-bellied Pitta Erythropitta erythrogaster complex form a discrete clade (Irestedt et al. 2013), with the much more distinctive Sula Islands form dohertyi basal to this clade (all considered conspecific by Gill and Donsker 2016, IOC v.6.3). Although the Sangihe form caeruleitorques and Siau form palliceps show morphological differences that led to their separation as species under a 7-point system (Collar et al. 2015), these are not deemed to be at the species level by WGAC and Clements et al. (2023), and hence caeruleitorques and palliceps are now considered subspecies of E. celebensis.

English names: The English name chosen, Sulawesi Pitta, is widely familiar (e.g.,through use by Gill and Donsker 2016, IOC v.6.3, although here explicitly not including Sula Pitta E. dohertyi) and appropriate for the region involved.

Restinga Antwren Formicivora littoralis is lumped into Serra Antwren F. serrana (Clements 2007:297)

Summary: The extremely range- and habitat-restricted Restinga Antwren of the coast of Rio de Janeiro does not fulfill the definition of a species, and is now considered part of the Serra Antwren species.

Details: Originally named as a new subspecies of Formicivora serrana by Gonzaga and Pacheco (1990), F. littoralis has been considered a full species based on its somewhat different morphology and distinctive, highly restricted habitat (Ridgely and Tudor 1994). However, Firme and Raposo (2011) showed that F. littoralis falls morphologically at the end of a cline and vocally is very similar to other taxa in the F. serrana complex, and that littoralis is thus

better treated as a subspecies. del Hoyo and Collar (2016) treated it thus, and WGAC and Clements et al. (2023) align on this treatment.

English names: The name Restinga Antwren is now limited to use as a group name within Serra Antwren.

Puna Canastero Asthenes sclateri is lumped into Streak-backed Canastero A. wyatti (Clements 2007:276)

Summary: Two confusing canasteros of the high Andes are now treated as a single species, Streak-backed Canastero.

Details: Asthenes sclateri was originally described as a full species, and it was not even listed adjacent to A. wyatti in Peters (1951). While various treatments have been adopted in the complex, it has been shown that these are sister taxa (Derryberry et al. 2011, Harvey et al. 2020), although by no means have all subspecies been sampled. A seemingly broad region of intergradation has long been known in the Titicaca Basin (Fjeldså and Krabbe 1990), and ML photographs seem to confirm the variability of tail pattern in this region. Vocalizations are similar between sclateri and wyatti (as summarized in Vuilleumier 1997), as can be verified by perusal of ML recordings. Much further study is clearly needed, but at present there is little support for their treatment as two species, and del Hoyo and Collar (2016) united them, a treatment on which WGAC and Clements et al. (2023) now align.

English names: The name Puna Canastero is now used as a group name within the Streak-backed Canastero.

Cordilleran Flycatcher Empidonax occidentalis is lumped into Pacific-slope (now Western) Flycatcher E. difficilis (Clements 2007:334)

Summary: Birding has just become more straightforward in the western US and Mexico, with the long-anticipated lump of Pacific-slope and Cordilleran Flycatchers into Western Flycatcher.

Details: The Western Flycatcher Empidonax difficilis has had a particularly complicated taxonomic history; five subspecies were recognized by Traylor (1979a), but integrative taxonomic work (Johnson 1980, 1994, Johnson and Marten 1988) led to the treatment of E. occidentalis as a separate species. This treatment has come under increasing scrutiny due to the difficulty of identifying many individuals, and the fact that what is now known to be a large area of intergradation in southwestern Canada and nearby US states was overlooked in previous studies (Linck et al. 2019, Isacoff 2021, Hopping 2022, Hopping and Linck 2023 https://americanornithology.org/wp-content/uploads/2023/05/2023-D.pdf). NACC (Chesser et al. 2023), WGAC, Gill et al. (2023, IOC v.13.2), and Clements et al. (2023) now align in reverting to the earlier treatment of the complex as a single species, E. difficilis. Further study will be necessary to elucidate the relationships of the population of mountains of western Mexico, however.

English names: The names Cordilleran and Pacific-Slope Flycatchers will now be used only as group names of the long-established older name Western Flycatcher, following Chesser et al. (2023).

Western Square-tailed Drongo Dicrurus occidentalis is lumped into Sharpe’s Drongo D. sharpei (Clements 2007:577)

Summary: The Western Square-tailed Drongo of western African forests is now considered conspecific with Sharpe’s Drongo of central African forests.

Details: Dicrurus sharpei and D. ludwigii were both originally described as full species, and have long been recognized as conspecific (e.g., Vaurie 1949, 1962). However, the molecular and morphological analyses of Fuchs et al. (2017b, 2018a) suggested that D. sharpei is comprised of two species, of which D. occidentalis of the forests of western Africa was described as new to science (Fuchs et al. 2018b), and this treatment was adopted by Gill and Donsker (2019, IOC v.9.1) and Clements et al. (2021). Fishpool et al. (2021), however, showed that while D. ludwigii and D. sharpei are well-differentiated morphologically, D. occidentalis is not, and thus they argued that occidentalis should be considered a subspecies of sharpei. WGAC and Clements et al. (2023) agree that further evidence supporting the species status of occidentalis would be necessary.

English names: The name Western Square-tailed Drongo is now retired and Sharpe’s (Western) is the group name for D. sharpei occidentalis.

Glossy-backed Drongo Dicrurus divaricatus is lumped into Fork-tailed Drongo D. adsimilis (Clements 2007:578)

Summary: The African savanna drongos are now united as a single species, with Glossy-backed Drongo now a group in Fork-tailed Drongo.

Details: First described as a full species, Dicrurus divaricatus was the only subspecies of D. adsimilis recognized by Vaurie (1962), though earlier he (Vaurie 1949) had united D. modestus and its subspecies with D. adsimilis. del Hoyo and Collar (2016), however, stated that divaricatus and adsimilis intergrade, and thus they considered divaricatus a subspecies of D. adsimilis. Fuchs et al. (2018b), with extensive mtDNA sampling but weakly supported branches, suggested that D. divaricatus and D. adsimilis are paraphyletic, and hence they have been considered separate species (with the additional recognition of the subspecies lugubris) by most recent sources. However, WGAC and Clements et al. (2023) consider the situation with respect to the species status of G. divaricatus unresolved.

English names: The name Glossy-backed is now used for the divaricatus group within Fork-tailed Drongo D. adsimilis.

Fanti Drongo Dicrurus atactus is lumped into Velvet-mantled Drongo D. modestus (Clements 2007:578)

Summary: The West African forest drongo formerly known as Fanti Drongo is returned to subspecies status within the more widespread Velvet-mantled Drongo.

Details: Originally described as a subspecies of D. modestus, with much glossier upperparts (Oberholser 1899), and treated as such until recently (as in Vaurie 1962), an mtDNA analysis (Fuchs et al. 2017b, 2018b) suggested that D. atactus is not sister to D. modestus. However, D. atactus evidently intergrades extensively with D. modestus in southwestern Nigeria, leading del Hoyo and Collar (2016) to consider atactus a subspecies of D. modestus. WGAC and Clements et al. (2023) agree that further evidence is needed before atactus can be considered specifically distinct.

English names: The name Fanti Drongo is now used as a group name within Velvet-mantled Drongo D. modestus.

Bohol Sunbird Aethopyga decorosa and Mountain Sunbird A. jefferyi are lumped into Metallic-winged Sunbird A. pulcherrima (Clements 2007:542)

Summary: The Philippines loses two recognized endemic species of sunbird, Bohol Sunbird and Mountain Sunbird, which are now considered to be conspecific with Metallic-winged Sunbird.

Details: The three taxa of the Aethopyga pulcherrima complex (Rand 1967) that have recently been treated as species were all originally described as such. Aethopyga decorosa of Bohol and A. pulcherrima of the Eastern Visayas and Mindanao group are primarily lowland in distribution, while Luzon jefferyi is montane. Hosner et al. (2013) found very deep genetic divergences between them that led to their treatment as three species (e.g., Gill and Donsker 2012, IOC v.3.1; Clements et al. 2013, v.6.8), but the near-lack of morphological and vocal differences (Boesman 2016 [No. 342]) led del Hoyo and Collar (2016) to consider all a single species. WGAC, Gill et al. (2023), and Clements et al. (2023) now align on this treatment as well. Further study confirming deep molecular divergences or vocal or other differences might lead to subsequent change.

English names: The name Bohol Sunbird is now used only as a group name within Metallic-winged Sunbird, while Mountain Sunbird is retired and replaced with the Luzon group of Metallic-winged Sunbird.

Vincent’s Bunting Emberiza vincenti is lumped into Cape Bunting E. capensis (Clements 2007:665)

Summary: The Vincent’s Bunting of rocky areas mainly in Malawi is now considered a strongly marked subspecies group of the widespread Cape Bunting.

Details: Emberiza vincenti was first described as a subspecies of E. capensis, though with the remark that it “differs very strikingly” from all other taxa of that species in its highly saturated coloration (Lowe 1932). It was evidently first treated as specifically distinct by Fry et al. (2004), followed by Gill and Wright (2006, IOC v.1.0). It is considered to be vocally identical both in song and calls to other forms of E. capensis (Dowsett-Lemaire and Dowsett 2006, Turner and Pearson 2015), and del Hoyo and Collar (2016), WGAC, Clements et al. (2023), and Gill et al. (2023, IOC v.13.2) now align in considering vincenti a subspecies of E. capensis.

English names: The name Vincent’s Bunting is now retired except for use as a group within Cape Bunting.

Caqueta Seedeater Sporophila murallae is lumped into Wing-barred Seedeater S. americana (Clements 2007:670)

Summary: There is now one fewer species of seedeater with black-and-white plumage in western Amazonia, with the lump of Caqueta Seedeater into Wing-banded Seedeater.

Details: Originally described as a subspecies, S. murallae was elevated to species status based on Stiles (1996). It has now been shown that perceived differences and range discontinuity that led to this treatment were artifactual (https://www.museum.lsu.edu/~Remsen/SACCprop932.htm), and SACC has taken the step of reuniting murallae within S. americana, a treatment on which WGAC, Clements et al. (2023), and Gill et al. (2022, IOC v.12.2) have all now aligned.

English names: The English name Caqueta Seedeater is now in use only as a group name in eBird.

Standard Updates and Corrections

The section consists of a wide range of additional revisions, such as changes to family composition or English or scientific names that are not associated with a split or a lump; additions or deletions of subspecies; adjustments to the composition of groups; and revisions to the ranges of species or subspecies. Please note that all revisions also are documented in the eBird/Clements Checklist v2023 downloadable spreadsheet (Clements et al. 2023). Taxon numbers refer to the unique number for each taxon or group in Clements et al. (2023), and as they change from one version to the next are only for reference in this document and the Clements et al. (2023) spreadsheet.

Families

Family rows are added for each family, with the same set of codes and with English and scientific names.

Taxon 24623: The Family Hyliidae, the Hylias, has been split from Family Macrosphenidae, based on deep divergence and uncertain relationships (e.g., Oliveros et al. 2019a).

Taxon 24954: The Family Paradoxornithidae, the Parrotbills, is split from the Sylviidae (Cai et al. 2019).

Name Changes

Not including those mandated by taxonomic changes, discussed with each account above. Some minor name changes deemed not to require explanation beyond the comment in the spreadsheet (Clements et al. 2023) are not included here. The new names used in Clements et al. (2023) are denoted in boldface.

Taxon 618: The English name Marbled Teal Marmaronetta angustirostris is changed to Marbled Duck, as the species is not closely related to teals of the genus Anas (e.g., Kimball et al. 2019), and this name aligns with Gill and Wright (2006, IOC v.1.0) and other sources.

Taxa 1204, 1205: Verreaux’s Partridge Tetraophasis obscurus and Szechenyi’s Partridge Tetraophasis szechenyii are renamed Chestnut-throated Monal-Partridge and Buff-throated Monal-Partridge, respectively. These names are more descriptive and highlight a feature distinguishing the two sister species, as well as allying them with each other and with monals of the genus Lophophorus, now known to be sister to Tetraophasis (Chen et al. 2021). They combine the name “monal-partridge” used since Gill and Wright (2006, IOC v.1.0) with the descriptive species names long used by Oriental Bird Club (Inskipp et al. 1996). The group name Monal Partridge was also used in the first few editions of the Clements Checklist.

Taxon 1413: Hume’s Pheasant Syrmaticus humiae is changed to Mrs. Hume’s Pheasant, the form of the name that Hume (1880) bestowed on this hard-attained bird, which he named after his wife. This form of the name also aligns with Howard and Moore from the second edition, Gill and Wright (2006, IOC v.1.0), BirdLife International (although as Mrs rather than Mrs.).

Taxon 1935: The Japanese Wood-Pigeon Columba janthina now becomes Black Wood-Pigeon to better reflect its distinctive coloration and range, as it is a small-island specialist from Japan and South Korea through Taiwan. This name also has been long-used, including in Clements 3rd edition, and is familiar, and aligns with Gill et al. (2023, IOC v.13.2). The rare form found on the Ogasawara (Bonin) Islands and at least formerly on Iwo (Volcano) Islands, C. j. nitens, was considered a potential split and called Red-headed Woodpigeon by del Hoyo and Collar (2014) and Chikara (2019); there appear to be minor vocal differences and they are genetically isolated as expected based on distance (Seki et al. 2007).

Taxa 2202–2224: The ground dove genus Alopecoenus Sharpe, 1899 is junior to Pampusana Bonaparte, 1855, which has as its type species P. xanthonura (Temminck, 1823). Given that the former was only resurrected recently due to paraphyly in Gallicolumba (e.g., Burleigh et al. 2015), the latter must be used (Bruce et al. 2016; WGAC), and involves a change in gender.

Taxa 2540, 18304, 19608, 20372: Comoros Green-Pigeon Treron griveaudi, Comoros Cuckooshrike Coracina cucullata, Comoros Blue Vanga Cyanolanius comorensis, and Malagasy Paradise-Flycatcher (Comoros) are changed to Comoro Green-Pigeon, Comoro Cuckooshrike, Comoro Blue Vanga, and Malagasy Paradise-Flycatcher (Comoro) respectively, for consistency with Gill et al. (2023, IOC v.13.2).

Taxa 2933–2956: The small bustards formerly united in Eupodotis (Eupodotis senegalensis, E. caerulescens, E. vigorsii, E. rueppelii, E. humilis, E. savilei, E. gindiana, E. ruficrista, E. afra, and E. afraoides) are now treated by WGAC within four different genera due to non-monophyly of the genus Eupodotis sensu lato, as demonstrated by the tree of Pitra et al. (2002). Eupodotis senegalensis and Eupodotis caerulescens remain in that genus; the other generic groups are Heterotetrax vigorsii, Heterotetrax rueppelii, and Heterotetrax humilis; Lophotis savilei, Lophotis gindiana, and Lophotis ruficrista; and Afrotis afraand Afrotis afraoides. This accords with the generic treatment of del Hoyo and Collar (2014), but not completely with that of Burleigh et al. (2015), in which for example the very similar afra and afraoides (which are sister taxa in Pitra et al. 2002) are in different clades.

Taxa 2996–3007: Of the turacos formerly united in the genus Tauraco, the leucotis/ruspolii clade is now treated by WGAC as Menelikornis leucotis and Menelikornis ruspolii, and the porphyreolophus/johnstoni clade (of which the latter was formerly in Ruwenzorornis) as Gallirex porphyreolophus and Gallirex johnstoni, in concordance with the phylogeny of Perktaş et al. (2020). The continued treatment of the two species of Musophaga as a separate genus to the exclusion of T. macrorhyncha and T. verreauxi, however,does not agree with the Perktaş et al. (2020) tree, though it is intuitive on morphological grounds, and further study is required.

Taxa 3010–3018: The long-standing two-genus treatment of go-away-birds as Corythaixoides personatus, Corythaixoides concolor, and Corythaixoides leucogaster and plantain-eaters as Crinifer piscator and Crinifer zonurus is unsupported by molecular analyses (Njabo and Sorenson 2009, Perktaş et al. 2020). A three-genus treatment, with leucogaster in Criniferoides could be adopted, but given the relatively low genetic and morphological divergence levels, WGAC, Clements et al. (2023), and Gill et al. (2021, IOC v.11.1) now align on treating all the former Corythaixoides species within Crinifer, as Crinifer personatus, Crinifer concolor, and Crinifer leucogaster.

Taxa 3306, 9873: For consistency, the group name of Chrysococcyx lucidus harterti Shining Bronze-Cuckoo(Solomon Is.) is changed to Shining Bronze-Cuckoo (Solomons) and that of Todiramphus sacer [solomonis Group] Pacific Kingfisher (Solomon Is.) becomes Pacific Kingfisher (Solomons).

Taxon 3332: The White-crowned Koel Cacomantis leucolophus is now known to be a member of the Cacomantis clade, not the Eudynamys clade known as koels (Sorenson and Payne 2005). Thus, the English name changes to White-crowned Cuckoo, aligning with Gill and Wright (2006, IOC v.1.0).

Taxa 3697, 30208: The English names of Donaldson-Smith’s Nightjar Caprimulgus donaldsoni and of Donaldson-Smith’s Sparrow-Weaver Plocepasser donaldsoni were incorrectly hyphenated (Beolens et al. 2014) in previous versions, and are now Donaldson Smith’s Nightjar and Donaldson Smith’s Sparrow-Weaver, respectively, aligning with Gill and Donsker (2011, IOC v.2.10).

Taxa 3837–3838, 3845, 3852, 3907: The English names of Philippine Spinetailed Swift Mearnsia picina, Papuan Spinetailed Swift Mearnsia novaeguineae, White-rumped Needletail Zoonavena sylvatica, and Silver-rumped Needletail Rhaphidura leucopygialis are changed to Philippine Spinetail, Papuan Spinetail, White-rumped Spinetail, and Silver-rumped Spinetail, respectively. A sister relationship between these has not been established but the rationale for differing group names is obscure, confusion with furnariid spinetails seems unlikely, and this aligns with e.g., Gill et al. (2023, IOC v.13.2). With the above change, the English name “needletail sp.” is now exclusive to the large swifts of the genus Hirundapus.

Taxon 4027: The English name Polynesian Swiftlet Aerodramus leucophaeus is changed to Tahiti Swiftlet to better reflect its area of endemism, and to align with e.g., Gill and Wright (2006, IOC v.1.0).

Taxa 4053–4068, 4133: Alpine Swift Apus melba and Mottled Swift Apus aequatorialis are now placed in the genus Tachymarptis, as Tachymarptis melba and Tachymarptis aequatorialis respectively, based on morphological and feather louse differences (Brooke 1970, 1972) and phylogenetic data (Päckert et al. 2012), and now aligning with e.g., Gill and Wright (2006, IOC v.1.0).

Taxon 4069: The English name Alexander’s Swift for Apus alexandri is changed to Cape Verde Swift to emphasize the species’ distribution and align with e.g., Gill and Wright (2006, IOC v.1.0).

Taxa 5012–5020: The name Leucolia proposed for a clade of emerald hummingbirds (Stiles et al. 2017) was found to be preoccupied, and a new name Ramosomyia was thus proposed (Bruce and Stiles 2021). Violet-crowned Hummingbird Leucolia violiceps thus becomes Ramosomyia violiceps and Green-fronted Hummingbird Leucolia viridifrons becomes Ramosomyia viridifrons, aligning with Chesser et al. (2022) and Gill et al. (2022, IOC v.12.2).

Taxa 5186–5189: The English group names of Madagascar Wood-Rail Mentocrex kioloides and Tsingy Wood-Rail Mentocrex beankaensis are changed to Madagascar Forest Rail and Tsingy Forest Rail because these Malagasy taxa are not members of the New World Aramides Wood-Rail group, nor are they even the same family, while they are the sister group to the clade containing the Rallicula forest rails within the Sarothruridae (Boast et al. 2019, Stervander et al. 2019).

Taxa 5214–5225: The Chestnut Forest-Rail Rallina rubra, White-striped Forest-Rail R. leucospila, Forbes’s Rail R. forbesi, and Mayr’s Rail R. mayri of New Guinea are now recognized as only superficially similar to the true Rallina clade of Asia and to belong in the Saruthruridae based on morphological (Livezey 1998) and genetic evidence (Boast et al. 2019, García-R et al. 2020). They are returned to the genus Rallicula Schlegel, 1871, of which rubra is the type species (e.g., the treatment of Peters 1934, who however recognized only two species in Rallicula, treating forbesi and mayri as subspecies of R. leucospila). The English names are modified to add “Forest” to the group names of R. forbesi and R. mayri (as in Beehler and Pratt 2016), but without the hyphen since they evidently do not form a strictly monophyletic group with the Malagasy region forest rails of the genus Mentocrex, rather being sister to Sarothrura flufftails. The species are now: Chestnut Forest Rail Rallicula rubra, White-striped Forest Rail Rallicula leucospila, Forbes’s Forest Rail Rallicula forbesi, and Mayr’s Forest Rail Rallicula mayri, aligning with Gill and Donsker (2010, IOC v.2.6).

Taxa 5300, 5572: English names of the extinct rallids of St. Helena in the south Atlantic are reversed to align with Gill et al. (2023) and better reflect relationships. St. Helena Crake Atlantisia podarces is changed to St. Helena Rail because this species is thought to have evolved from Rallus (Olson 1973). Conversely, what was known as the St. Helena Rail Zapornia astrictocarpus changes from St. Helena Rail to St. Helena Crake because most Zapornia species are known as crakes. This resolves the previously confusing situation whereby both Gill and Donsker (2012, IOC v.3.1, but as Aphanocrex podarces rather than Atlantisia podarces) and Clements et al. (2022 and earlier versions) used the English names St. Helena Rail and St. Helena Crake, but the names were reversed in each list with respect to the scientific names.

Taxa 5398, 5586–5594: The scientific name of the Zapata Rail is changed from Cyanolimnas cerverai to Mustelirallus cerverai; the scientific name of the Ocellated Crake is changed from Micropygia schomburgkii to Rufirallus schomburgkii; the scientific name of the Russet-crowned Crake is changed from Anurolimnas viridis to Rufirallus viridis; and the scientific name of the Chestnut-headed Crake is changed from Anurolimnas castaneiceps to Rufirallus castaneiceps (Brown et al. 2022, Chesser et al. 2023, Gill et al. 2023, IOC v.13.2).

Taxa 5705–5710: The American thick-knees have been found to comprise an ancient lineage basal to other burhinids (Černý and Natale 2022), and have thus been given a new genus name, Hesperoburhinus Černý et al., 2023. Thus, the Double-striped Thick-knee Burhinus bistriatus becomes Hesperoburhinus bistriatus and Peruvian Thick-knee Burhinus superciliaris becomes Hesperoburhinus superciliaris (https://www.museum.lsu.edu/~Remsen/SACCprop976.htm).

Taxon 5794: Based on morphological and molecular evidence (Livezey 2010, Černý and Natale 2022), Pied Lapwing Vanellus cayanus is not closely related to lapwings, or to any other genus of plover. Its name is thus changed to Pied Plover Hoploxypterus cayanus, without necessarily implying close relationships to any of the disparate groups called plovers, and aligns with Gill and Wright (2006, IOC v.1.0).

Taxon 5796: The Rufous-chested Dotterel Charadrius modestus has been shown to be deeply diverged sister taxon to the dissimilar-looking Phegornis mitchellii (Černý and Natale 2022), and the two are best retained in separate genera. Zonibyx is resurrected for modestus, and hence Charadrius modestus becomes Zonibyx modestus, as in Peters (1934) and the first edition of Clements.

Taxon 5797: The Eurasian Dotterel Charadrius morinellus is now known to be a very deeply diverged lineage that is sister to Charadrius sensu stricto (Černý and Natale 2022). It is thus now known by the resurrected genus name Eudromias morinellus, as in Peters (1934), the first edition of Clements, and Dickinson and Remsen (2013).

Taxa 5808–5910: Three monotypic genera, Hooded Plover Thinornis cucullatus, Shore Plover Thinornis novaeseelandiae, and Black-fronted Dotterel Elseyornis melanops have been shown to be embedded in the Charadrius sensu stricto lineage (Černý and Natale 2022), and thus are now known as Charadrius cucullatus, Charadrius novaeseelandiae, and Charadrius melanops, respectively.

Taxa 5834, 5835: The English name White-headed Lapwing Vanellus albiceps is altered to White-crowned Lapwing to better reflect the bird’s identifying marks, and to align with prevailing usage, including Gill and Wright (2006, IOC v.1.0).

Taxa 5872–5928: The lineage of the former Charadrius plovers containing these taxa has been conclusively shown to be deeply paraphyletic (e.g., Černý and Natale 2022), and the genus Anarhynchus is now used for all these species (rather than several small or monotypic genera).

Taxa 6987, 8055, 28260: The English name New Caledonia Goshawk Accipiter haplochrous is changed to New Caledonian Goshawk and the group names for Gould’s Petrel (New Caledonia) Pterodroma leucoptera caledonica and Island Thrush (New Caledonia) Turdus poliocephalus xanthopus are changed to Gould’s Petrel (New Caledonian) and Island Thrush (New Caledonian) for consistency with other species named for that island.

Taxon 7311: The White-crested Bittern Tigriornis leucolopha of African forests has now been shown to be sister to the Neotropical Tigrisoma tiger-herons (Hruska et al. 2023), and thus its group name changes to reflect that relationship, now being known as White-crested Tiger-Heron.

Taxa 7364–7396, 7435–7438: Night Herons are now known to not be a monophyletic group (Hruska et al. 2023), and hence the hyphen between Night and Heron is now dropped in the English names of all species of Nyctanassa, Nycticorax, Gorsachius, Calherodius, and Oroanassa.

Taxa 7933–7940: The taxa normally called “marsh-harriers” do not form an exclusive monophyletic group with respect to others that do not bear the group name “Marsh” (Oatley et al. 2015), and hence the hyphen is removed. Eurasian Marsh-Harrier Circus aeruginosus, which occurs mostly in western Eurasia and Africa, is changed to Western Marsh Harrier; African Marsh-Harrier Circus ranivorus becomes African Marsh Harrier, Eastern Marsh-Harrier Circus spilonotus becomes Eastern Marsh Harrier, and Papuan Marsh-Harrier Circus spilothorax becomes Papuan Harrier.

Taxa 8192–8201: The two main sea- and fish-eagle clades often all treated as Haliaeetus (Mindell et al. 2018) divide into the mostly larger high-latitude Haliaeetus and the mostly smaller tropical Icthyophaga group, with associated plumage and vocal differences, and are now recognized as two genera by WGAC and now aligned in Clements et al. (2023) and Gill et al. (2023, IOC v.13.2). The spelling is Icthyophaga, not Ichthyophaga, as case 3603 to ICZN (Williams and Bunkley-Williams 2017, ICZN 2017).

Taxa 8758–8783: The eagle-owl genus Ketupa is feminine (Dickinson and Remsen 2013) and thus the gender of the following names must be corrected, as follows: Ketupa leucostictus to Ketupa leucosticta; Ketupa lacteus to Ketupa lactea; Ketupa coromandus to Ketupa coromanda; and Ketupa sumatranus to Ketupa sumatrana.

Taxa 9251–9252: Recent molecular phylogenetic analyses (Hosner et al. 2010, Oliveros et al. 2019b) align with morphological and vocal differences to show that Apalharpactes is of unclear relationships with respect to, and perhaps not closely related to Harpactes, and thus Javan Trogon Harpactes reinwardtii becomes Apalharpactes reinwardtii, and Sumatran Trogon Harpactes mackloti becomes Apalharpactes mackloti, as in Gill and Wright (2006, IOC v.1.0).

Taxon 9499: The phylogenetic relationships of the highly morphologically, vocally, and behaviorally apomorphic Helmeted Hornbill Buceros vigil remain unclear (Viseshakul et al. 2011, Gonzalez et al. 2013), but it is clearly a strongly diverged lineage, and thus Rhinoplax vigil is now used for this species, as with Gill and Wright (2006, IOC v.1.0).

Taxa 10337–10340: The Green Barbet Stactolaema olivacea is evidently not sister to other Stactolaema barbets (Moyle 2004), and hence is now known as Cryptolybia olivacea.

Taxa 10459–10467: The genus Lybius is evidently paraphyletic (Moyle 2004) with respect to Tricholaema. The large, “toothed” barbets Brown-breasted Barbet Lybius melanopterus, Black-backed Barbet Lybius minor, Double-toothed Barbet Lybius bidentatus, Bearded Barbet Lybius dubius, and Black-breasted Barbet Lybius rolleti share similarities in voice and sexual dimorphism and are now placed by WGAC in Pogonornis, as Pogonornis melanopterus, Pogonornis minor, Pogonornis bidentatus, Pogonornis dubius, and Pogonornis rolleti.

Taxon 10501: The Little Barbet Psilopogon australis of Java and Bali is now known as Yellow-eared Barbet, to better reflect its plumage differences from former conspecifics, and to align with e.g., Gill and Donsker (2014, IOC v.4.4).

Taxa 11057–11095: The Afrotropical woodpecker genus Chloropicus has been shown in multiple studies (e.g., Fuchs et al. 2017a, Shakya et al. 2017) to be comprised of two deeply genetically divergent clades. Given this and that the three species within the narrowly defined Chloropicus are readily defined morphologically, the remaining Afrotropical species are placed within Dendropicos.

Taxon 11294: The Sundaic Orange-backed Woodpecker Reinwardtipicus validus is sister to Chrysocolaptes (Benz et al. 2006, Fuchs et al. 2017a), though moderately diverged genetically and morphologically, and is now placed within that genus as Chrysocolaptes validus.

Taxon 11372: The Olive-backed Woodpecker Dinopium rafflesii has been found to be fairly closely related to members of the genus Gecinulus (Shakya et al. 2017). Though differing in some aspects of plumage it is similar in vocalizations and is now placed within that genus as Gecinulus rafflesii.

Taxa 11469–11476: Paraphyly of Campethera with Geocolaptes (Fuchs et al. 2017a) is avoided by treating Brown-eared Woodpecker Campethera caroli and Buff-spotted Woodpecker Campethera nivosa within the genus Pardipicus, as Pardipicus caroli and Pardipicus nivosus (Dowsett and Gregory 2022).

Taxon 11943: The Pink CockatooLophochroa leadbeateri is a fairly close sister to Cacatua (Smith et al. 2022), to which it is similar morphologically and in vocalizations, and is thus now recognized within that genus as Cacatua leadbeateri, as in Gill and Wright (2006, IOC v.1.0).

Taxon 12074: With the four-way split of the Eclectus Parrot Eclectus roratus and use of Eclectus as the group name, the English name of the extinct Oceanic Parrot Eclectus infectus is changed to Oceanic Eclectus.

Taxon 12103:  The specific epithet of the extinct Mascarene Parrot Mascarinus mascarin has been deemed to represent an abbreviation in the original description (https://www.iczn.org/cases/resolved-opinion-issued/case/3715). Opinion 2455 states that the species-group name mascarinus is conserved as a justified emendation; thus the taxon is now known as Mascarinus mascarinus.

Taxa 12266–12279: The three-genus treatment as 1) Red-rumped Parrot Psephotus haematonotus; Mulga Parrot Psephotus varius, Hooded Parrot Psephotus dissimilis, Golden-shouldered Parrot Psephotus chrysopterygius, and Paradise Parrot Psephotus pulcherrimus; 2) Red-capped Parrot Purpureicephalus spurius; and 3) Greater Bluebonnet Northiella haematogaster; Naretha Bluebonnet Northiella narethae is untenable based on phylogenetic analyses (Irestedt et al. 2019, Smith et al. 2022). The amount of morphological variation encompassed by an expanded Psephotus is deemed excessive and hence a four-genus treatment is adopted, with four of the species in Psephotus moved to Psephotellus, as follows: Psephotellus varius, Psephotellus dissimilis, Psephotellus chrysopterygius, and Psephotellus pulcherrimus.

Taxon 12408: For the Ornate Lorikeet Saudareos ornatus, the gender ending must be corrected to feminine (Joseph et al. 2020), as Saudareos ornata.

Taxa 13057–13062: The name Blue-breasted Pitta Erythropitta erythrogaster is changed to Philippine Pitta, and the groups are now Philippine Pitta (Philippine) and Philippine Pitta (Talaud).

Taxon 15180: The Speckled Spinetail Cranioleuca gutturata has been shown to be embedded within Thripophaga (Harvey et al. 2020) and is hence transferred to that genus, as Thripophaga gutturata.

Taxon 15192:  The Russet-mantled Softtail Thripophaga berlepschi has been shown to be embedded within Cranioleuca (Harvey et al. 2020) and is hence transferred to that genus, as Cranioleuca berlepschi.

Taxon 15268: The still-undescribed bird informally referred to as Araguaia River Spinetail (undescribed form) Certhiaxis [undescribed form] is now called Tocantins Spinetail (undescribed form) to distinguish it from the newly split Araguaia Spinetail Synallaxis simoni.

Taxa 15947, 15954: The group names of the Serra do Mar Tyrannulet Pogonotriccus difficilis and the Sao Paulo Tyrannulet Pogonotriccus paulista are changed such that all members currently recognized as members of the genus Pogonotriccus are now called bristle-tyrants, as Serra do Mar Bristle-Tyrant and Sao Paulo Bristle-Tyrant (https://www.museum.lsu.edu/~Remsen/SACCprop959.htm).

Taxa 16170–16212: The group names of all species of Tolmomyias are changed from Flycatcher to Flatbill (https://www.museum.lsu.edu/~Remsen/SACCprop974.htm).Thus, the English names are now Yellow-olive Flatbill Tolmomyias sulphurescens, Orange-eyed Flatbill Tolmomyias traylori, Yellow-winged Flatbill Tolmomyias flavotectus, Yellow-margined Flatbill Tolmomyias assimilis, Gray-crowned Flatbill Tolmomyias poliocephalus, Olive-faced Flatbill Tolmomyias viridiceps, and Ochre-lored Flatbill Tolmomyias flaviventris.

Taxa 16310–16322: Nesotriccus is masculine and hence gender for Tumbes Tyrannulet Nesotriccus tumbezana and its subspecies Nesotriccus tumbezana tumbezana and Nesotriccus tumbezana inflava; Marañon Tyrannulet Nesotriccus maranonica; the group Tumbes/Marañon Tyrannulet Nesotriccus tumbezana/maranonica; Northern Mouse-colored Tyrannulet Nesotriccus incomta and its subspecies Nesotriccus incomta eremonoma and Nesotriccus incomta incomta; Southern Mouse-colored Tyrannulet Nesotriccus murina and its subspecies Nesotriccus murina wagae and Nesotriccus murina murina and the group Northern/Southern Mouse-colored Tyrannulet Nesotriccus incomta/murina are corrected to Nesotriccus tumbezanus, Nesotriccus tumbezanus tumbezanus, Nesotriccus tumbezanus inflavus; Nesotriccus maranonicus and Nesotriccus tumbezanus/maranonicus; Nesotriccus incomtus, Nesotriccus incomtus eremonomus, and Nesotriccus incomtus incomtus; Nesotriccus murinus, Nesotriccus murinus wagae and Nesotriccus murinus murinus; and Nesotriccus incomtus/murinus.

Taxon 17230:  The Golden Bowerbird Amblyornis newtoniana has numerous plumage, egg character, and bower type differences that, in addition to its rather deep sister group divergence from Amblyornis (Ericson et al. 2020), support its return to the monotypic genus Prionodura, as Prionodura newtoniana, now aligning with Gill and Wright (2006, IOC v.1.0).

Taxon 17497–17501: The bearded honeyeaters of the New Guinea highlands are in two widely separated lineages (Beehler and Pratt 2016, Marki et al. 2017, Andersen et al. 2019, Hay et al. 2022) and are hence only convergently similar. Thus, both English and scientific names of Sooty Melidectes Melidectes fuscus including its subspecies Melidectes fuscus occidentalis and Melidectes fuscus fuscus; Short-bearded Melidectes Melidectes nouhuysi; and Long-bearded Melidectes Melidectes princeps change to Sooty Honeyeater Melionyx fuscus; Short-bearded Honeyeater Melionyx nouhuysi; and Long-bearded Honeyeater Melionyx princeps.

Taxa 17814–17816, 17872–17879, 18012: Based on phylogenetic results of Marki et al. (2017) and Norman et al. (2018), the following species of Acanthizidae should be placed in Aethomyias: Bicolored Mouse-Warbler Crateroscelis nigrorufa, now Aethomyias nigrorufus;Vogelkop Scrubwren Sericornis rufescens, now Aethomyias rufescens; Buff-faced Scrubwren Sericornis perspicillatus, now Aethomyias perspicillatus; Papuan Scrubwren Sericornis papuensis, now Aethomyias papuensis; Gray-green Scrubwren Sericornis arfakianus, now Aethomyias arfakianus; and Pale-billed Scrubwren Sericornis spilodera, now Aethomyias spilodera.

Taxon 18162: The sole New Guinea representative of the Pomatostomidae, the Papuan BabblerPomatostomus isidorei is genetically (Edwards and Wilson 1990, Burleigh et al. 2015), ecologically, and morphologically divergent to the extent that it is returned to the genus Garritornis, as Garritornis isidorei, aligning as such with Gill and Wright (2006, IOC v.1.0).

Taxon 19408: The relationships of the Black Butcherbird Cracticus quoyi with other Cracticus are not clear, with apparent paraphyly with the dissimilar Gymnorhina tibicen (Kearns et al. 2013, Cake et al. 2018), hence it is now placed in the monotypic genus Melloria as Melloria quoyi.

Taxon 19478:  For consistency with other taxa, the group name of Boulton’s Batis (Angolan) Batis margaritae margaritaeis changed to Boulton’s Batis (Angola).

Taxon 20025: Due to the lump of Western Square-tailed Drongo Dicrurus occidentalis into Sharpe’s Drongo D. sharpei and the use of the earlier common name Sharpe’s Drongo for both, the English name Common Square-tailed Drongo Dicrurus ludwigiiis changed to Square-tailed Drongo.

Taxa 20252–20256: The genus of the Wilson’s Bird-of-Paradise Cicinnurus respublica and Magnificent Bird-of-Paradise Cicinnurus magnificus is changed to Diphyllodes, as Diphyllodes respublica and Diphyllodes magnificus. This is based on the moderately deep genetic divergence of Diphyllodes from Cicinnurus (Irestedt et al. 2009)and the numerous plumage differences from the King Bird-of-Paradise Cicinnurus regius that they exhibit.

Taxon 20257–20259:  The genus of the Blue Bird-of-Paradise Paradisaea rudolphi is changed to Paradisornis, as Paradisornis rudolphi, based on the relatively deep divergence of Paradisornis from Paradisaea (Irestedt et al. 2009, Stelbrink et al. 2022) and its highly apomorphic plumage, display, and vocalizations.

Taxa 20282–20292, 21526–21535: The group name hyphen is removed from the monarchine Blue-headed Crested-Flycatcher Trochocercus nitens and the African Crested-Flycatcher Trochocercus cyanomelas, which are now Blue-headed Crested Flycatcher and African Crested Flycatcher, and from the stenostirine Dusky Crested-Flycatcher Elminia nigromitrata, White-bellied Crested-Flycatcher Elminia albiventris, and White-tailed Crested-Flycatcher Elminia albonotata, which are now Dusky Crested Flycatcher, White-bellied Crested Flycatcher, and White-tailed Crested Flycatcher. This change is enacted because the genera Trochocercus and Elminia do not form a monophyletic group.

Taxa 20331–20337: The English name Japanese Paradise-Flycatcher Terpsiphone atrocaudata is returned to the long-established and apt Black Paradise-Flycatcher to better reflect its distribution. A major part of its breeding range is in South Korea, and its wintering distribution extends to the northern Philippines and the Malayan Peninsula and occasionally farther south.

Taxa 20372, 23210, 24190, 28444, 29978, 30417: For consistency, English names are changed from Malagasy Paradise-Flycatcher (Grand Comoro) Terpsiphone mutata comorensis, Grand Comoro Brush-Warbler Nesillas brevicaudata, Grand Comoro Bulbul Hypsipetes parvirostris, Grand Comoro Flycatcher Humblotia flavirostris, Malagasy Sunbird (Grand Comoro) Cinnyris notatus moebii, and Red-headed Fody (Grand Comoro) Foudia eminentissima consobrina to Malagasy Paradise-Flycatcher (Grande Comore), Grande Comore Brush-Warbler, Grande Comore Bulbul, Grande Comore Flycatcher, Malagasy Sunbird (Grande Comore), and Red-headed Fody (Grande Comore), respectively.

Taxon 20627: Although there are only two species in the Papuan family Melampittidae, they differ from each other greatly in numerous morphological, ecological, and vocal characteristics (e.g., Mayr 1931b, Schodde and Christidis 2014) and they are rather more deeply diverged than for typical genera (McCullough et al. 2022). Thus, the Greater Melampitta Melampitta gigantea is now placed in the genus Megalampitta, as Megalampitta gigantea.

Taxa 20628–20632: The English name for Family Platylophidae is changed from Platylophidae (Crested Shrikejay) to Platylophidae (Crested Jayshrike) and the English name of the species is changed from Crested Shrikejay Platylophus galericulatus to Crested Jayshrike, which aligns with Gill et al. (2023). The relationships of this deeply diverged, monospecific family remain unclear (Gaudin et al. 2021).

Taxa 21387–21408: The English and generic names of the Papuan Flycatcher Microeca papuana are changed to Canary Flyrobin Devioeca papuana; the generic name of the Olive Flyrobin Microeca flavovirescens is changed to Kempiella flavovirescens; the English group and generic names of the Yellow-legged Flycatcher Microeca griseoceps are changed to Yellow-legged Flyrobin Kempiella griseoceps; the English group and generic names of the Yellow-bellied Robin Eopsaltria flaviventris are changed to Yellow-bellied Flyrobin Cryptomicroeca flaviventris; the English group name of the Torrent Flycatcher Monachella muelleriana is changed to Torrent Flyrobin; and the English group name of the Lemon-bellied Flycatcher Microeca flavigaster is changed to Lemon-bellied Flyrobin. The changes to generic names are due to improved understanding of relationships based on Loynes et al. (2009), Christidis et al. (2011), and Fjeldså et al. (2020), while the changes to English group names align with other sources and allow better expression of relationships for a well-supported clade within the Petroicidae with the use of the name flyrobin.

Taxa 21429–21432: The scientific name of the Black-chinned Robin Poecilodryas brachyura is changed to Heteromyias brachyurus based on morphological characters, following Beehler and Pratt (2016).

Taxa 21433–21436: The genus name of the Black-throated RobinPoecilodryas albonotata is changed to Plesiodryas albonotata, following Christidis et al. (2011), Dickinson and Christidis (2014), Beehler and Pratt (2016), del Hoyo and Collar (2016), and Gill and Donsker (2019, IOC v.9.2).

Taxa 21451–21453: The genus of White-rumped Robin Peneothello bimaculata is changed to Melanodryas, as Melanodryas bimaculata, in accord with the phylogeny of Fjeldså et al. (2020).

Taxon 21472:  The English and generic names of the Olive-yellow Robin Poecilodryas placens are changed to Banded Yellow Robin Eopsaltria placens, based on phylogenetic results of Christidis et al. (2011) and Fjeldså et al. (2020).

Taxa 21480–21493: The genus of Pale-yellow Robin Tregellasia capito and White-faced Robin Tregellasia leucops is changed to Eopsaltria, as Eopsaltria capito and Eopsaltria leucops, respectively, in accord with the phylogeny of Fjeldså et al. (2020).

Taxon 22143: The English name Latakoo Lark of Mirafra cheniana is changed to Melodious Lark, now aligning with  Gill and Wright (2006, IOC v.1.0).

Taxon 22144–22166, 22172: The English name Horsfield’s Bushlark Mirafra javanica is changed to Singing Bushlark, now aligning with Gill et al. (2023, IOC v.13.2).

Taxon 22359: The English name Razo Skylark Alauda razae is changed to Raso Skylark, the modern name of the island to which it is endemic, now aligning with Gill and Wright (2006, IOC v.1.0).

Taxon 23481: The specific epithet of the New Caledonian Grassbird Cincloramphus mariei is corrected to Cincloramphus mariae; the former was an unjustified emendation of the protonym Megalurulus mariae (Dickinson and Christidis 2014; Gill et al. 2023), although the species was evidently named for Edouard Auguste Marie (Beolens et al. 2014).

Taxa 23492–23496: Striated Grassbird was erroneously placed in Cincloramphus as Cincloramphus palustris in Clements et al. (2022); the correct genus name Megalurus palustris is restored (Alström et al. 2018).

Taxon 23621:  Brazza’s Martin Phedina brazzae has been long known to be quite distinct from Mascarene Martin Phedina borbonica (Wolters 1971, Brooke 1972, Mills and Cohen 2007), and is deeply diverged genetically (Sheldon et al. 2005, Brown 2019). Thus, it is now placed by WGAC in Phedinopsis Wolters, 1971 as Phedinopsis brazzae, aligning with Gill et al. (2021, IOC v.11.2).

Taxon 23642–23647:  The English name of the Pale Sand Martin Riparia diluta is changed by WGAC to Pale Martin, now aligning with Gill and Wright (2006, IOC v.1.0).

Taxon 24071–24074: The genus of Striated Bulbul Pycnonotus striatus is changed by WGAC to Alcurus Blyth, 1843, as Alcurus striatus, based on e.g., Shakya and Sheldon (2017) and now aligning with Gill et al. (2020, IOC v.10.2).

Taxon 24075: The genus of Finsch’s Bulbul Alophoixus finschii is changed by WGAC to Iole Blyth, 1844, as Iole finschii, based on e.g., Shakya and Sheldon (2017) and now aligning with Gill et al.  (2020, IOC v.10.2).

Taxon 24107–24110: The genus of Yellow-browed Bulbul Iole indica is changed by WGAC to Acritillas Oberholser, 1905, as Acritillas indica, now aligning with Gill and Wright (2006, IOC v.1.0).

Taxon 24111: The genus of Cream-striped Bulbul Pycnonotus leucogrammicus is changed by WGAC to Ixos Temminck, 1825 as Ixos leucogrammicus, based on e.g., Shakya and Sheldon (2017).

Taxon 24125: The genus of Nicobar Bulbul Hypsipetes nicobariensis is changed by WGAC to Ixos Temminck, 1825 as Ixos nicobariensis, now aligning with Gill and Wright (2006, IOC v.1.0).

Taxa 24193–24207: The genera of Puff-backed Bulbul Brachypodius eutilotus, Black-and-white Bulbul Brachypodius melanoleucos, Yellow-wattled Bulbul Brachypodius urostictus, Gray-headed Bulbul Brachypodius priocephalus, Black-headed Bulbul Brachypodius melanocephalos, Andaman Bulbul Brachypodius fuscoflavescens, and Blue-wattled Bulbul Pycnonotus nieuwenhuisii  are changed to Microtarsus Eyton, 1839. They become Microtarsus eutilotus, Microtarsus melanoleucos, Microtarsus urostictus, Microtarsus priocephalus, Microtarsus melanocephalos, Microtarsus fuscoflavescens, and Microtarsus nieuwenhuisii, respectively, based on e.g., Shakya and Sheldon (2017) and a general WGAC preference for broad genera (and thus differing from the treatment in Gill et al. 2023, IOC v.13.2).

Taxon 24231: The gender ending of Black-capped Bulbul Rubigula melanicterus is corrected to Rubigula melanictera.

Taxon 24653–24657: Based on divergence estimates in Alström et al. (2011) and the phylogeny in Fjeldså et al. (2020:220), the genus of Neumann’s Warbler Urosphena neumanni and Pale-footed Bush Warbler Urosphena pallidipes is changed by WGAC to Hemitesia Chapin, 1948, as Hemitesia neumanni and Hemitesia pallidipes, respectively. The former aligns with Gill and Wright (2006, IOC v.1.0) and the latter with Gill et al. (2023, IOC v.13.2).

Taxon 24842: The family name of Sylviidae is changed by WGAC from Sylviid Warblers, Parrotbills, and Allies to Sylviid Warblers and Allies, with the treatment of Parrotbills Paradoxornithidae as a separate family.

Taxon 24994:  The English name Streak-throated Fulvetta Fulvetta manipurensis is changed to Manipur Fulvetta, now aligning with Gill and Wright (2006, IOC v.1.5).

Taxa 25033–25036, 25063–25085: The genera Neosuthora, Chleuasicus, and Sinosuthora are placed by WGAC within Suthora, such that the Short-tailed Parrotbill Neosuthora davidiana is now Suthora davidiana; the Pale-billed Parrotbill Chleuasicus atrosuperciliaris is now Suthora atrosuperciliaris; Spectacled Parrotbill Sinosuthora conspicillata is now Suthora conspicillata; Gray-hooded Parrotbill Sinosuthora zappeyi is now Suthora zappeyi; Eye-ringed Parrotbill Sinosuthora [brunnea] ricketti is now Suthora ricketti; Brown-winged Parrotbill Sinosuthora brunnea is now Suthora brunnea; Vinous-throated Parrotbill Sinosuthora webbiana is now Suthora webbiana; and Ashy-throated Parrotbill Sinosuthora alphonsiana is now Suthora alphonsiana.

Taxa 28354, 29878: The English names Mariqua Flycatcher of Bradornis mariquensis and Mariqua Sunbird of Cinnyris mariquensis are changed to Marico Flycatcher and Marico Sunbird, respectively. These species were evidently named for the river generally now spelled River Marico, and this spelling aligns with Gill and Wright (2006, IOC v.1.5).

Taxon 28545: The White-tailed Flycatcher Cyornis concretus has been shown in several phylogenetic analyses to be a very divergent branch within Niltavinae (e.g., Sangster et al. 2010, 2021b, Zhao et al. 2023), and is thus now placed by WGAC in the new genus Leucoptilon Sangster et al., 2021, as Leucoptilon concretum, aligning with Gill et al. (2022, IOC v.12.1).

Taxon 28619:  The English name Pale-chinned Blue Flycatcher Cyornis poliogenys is changed to Pale-chinned Flycatcher because the species lacks blue in both sexes, as do several other members of the genus as now constituted.

Taxon 28699: The English name of this category is changed from blue flycatcher sp. to Cyornis sp., since not all species are blue.

Taxon 29163: The White-winged Cliff-Chat Thamnolaea semirufa has been shown to be a Monticola rock-thrush (Zuccon and Ericson 2010a, b), and is now Monticola semirufus, as agreed by WGAC and in alignment with Gill and Donsker (2010, IOC v.2.7).

Taxon 29295: The specific epithet of Heuglin’s Wheatear Oenanthe heuglini is corrected to Oenanthe heuglinii (van den Elzen et al. 2011), and now aligns with e.g., Gill et al. (2021, IOC v.11.2).

Taxon 31136: The White-rumped Snowfinch Montifringilla taczanowskii was formerly placed in the monotypic genus Onychostruthus Richmond, 1917 (e.g., Mayr 1927) as Onychostruthus taczanowskii, and this treatment, which receives support from phylogenetic analyses (Qu et al. 2006, Gebauer et al. 2006), and is adopted here, and now aligns with Gill and Wright (2006, IOC v.1.0).

Taxa 31137–31147: Phylogenetic analyses (Qu et al. 2006, Gebauer et al. 2006) provide some support for the recognition of the genus Pyrgilauda Bonaparte, 1850. Pere David’s Snowfinch Montifringilla davidiana now becomes Pyrgilauda davidiana; Rufous-necked Snowfinch Montifringilla ruficollis becomes Pyrgilauda ruficollis; Blanford’s Snowfinch Montifringilla blanfordi becomes Pyrgilauda blanfordi; and Afghan Snowfinch Montifringilla theresae becomes Pyrgilauda theresae; this treatment now aligns with Gill and Wright (2006, IOC v.1.0).

Taxon 31369: The Yellowish Pipit Anthus lutescens was long known as Anthus chii, and although Zimmer (1953) argued for the use of this name, it has long been known as A. lutescens. Smith and Clay (2021) reevaluated the issue and concluded that Anthus chii is the valid name, as now agreed by SACC (https://www.museum.lsu.edu/~Remsen/SACCprop910.htm).

Taxon 33956:  The Crimson-collared Grosbeak Rhodothraupis celaeno of northeastern Mexico has now been shown to be closely related to the similar-looking but widely disjunct Red-and-black Grosbeak Periporphyrus celaeno of northeastern South America (Barker et al. 2015, Bocalini et al. 2021), and is thus now treated as Periporphyrus celaeno by Chesser et al. (2023), WGAC, and Clements et al. (2023). A SACC proposal (https://www.museum.lsu.edu/~Remsen/SACCprop970.htm) is in progress.

Taxa 34831–34835: The Slaty Finch Spodiornis rusticus is now known to form a clade with certain other small plain gray or brown finches that occur mainly in bamboo (Burns et al. 2014; Barker et al. 2015), but relationships are not yet well-supported and nomenclatural issues suggest caution. For alignment with e.g., NACC and Gill and Wright (2006, IOC v.1.0), the scientific name becomes Haplospiza rustica.

Subspecies Changes: Additions, Deletions, or Moves

Taxa 1677.1–1677.5: Clements has been the only major global avian checklist to treat Common Quail Coturnix coturnix as monotypic, whereas the others recognize a variable array of subspecies. After review (e.g., Zedlitz 1912, Hartert 1917, Clancey 1976), Clements et al. (2023) now aligns with Gill et al. (2023) in recognizing the nominate Coturnix coturnix coturnix, Coturnix coturnix conturbans of the Azores, Coturnix coturnix inopinata of Cabo Verde, Coturnix coturnix erlangeri of eastern Africa, and Coturnix coturnix africana of southern Africa. The putative Madeira subspecies Coturnix coturnix confisa is considered to be an artifact (Fontoura and Gonçalves 1995).

Taxon 2087: The smaller Sri Lankan form ceylonensis of Spotted Dove Spilopelia chinensis in the suratensis group is now recognized as Spilopelia chinensis ceylonensis (Rasmussen and Anderton 2012).

Taxa 3365.5, 3367.5, 3370.5: Based on the exhaustive analyses of Wu et al. (2022), three additional subspecies are now recognized in the Brush Cuckoo Cacomantis variolosus complex and one is synonymized. The additional subspecies now recognized are Cacomantis variolosus major of the northern Moluccas; Cacomantis variolosus obscuratus of Numfor, in Cenderawasih Bay, off northwestern New Guinea; and Cacomantis variolosus fortior of the D’Entrecasteaux Archipelago, off southeastern New Guinea. The subspecies oreophilus of east and south New Guinea is synonymized with infaustus following Wu et al. (2022). At the time of finalization the changes in species rank proposed by Wu et al. (2022) had not been evaluated; these will be addressed in the 2024 update.

Taxon 4127: TheHorus Swift Apus horus was formerly considered to have a dark-rumped subspecies, A. h. fuscobrunneus from Angola, but this now been shown to be essentially indistinguishable from the rare but widespread dark morph of A. horus (Jansen and Driessens 2023). Thus, A. horus is now considered monotypic but with two groups.

Taxon 5216: We follow Beehler and Pratt (2016) in synonymizing subspecies Chestnut Forest Rail Rallicula rubra telefolminensis with Rallina rubra klossi.

Taxon 5222: We follow Beehler and Pratt (2016) in synonymizing Forbes’s Forest Rail subspecies Rallicula forbesi steiniwith Rallicula forbesi forbesi. We tentatively continue to recognize Rallicula forbesi dryas, however, given the discussion in Pratt (1982) and that no rationale was given for its synonymy in Beehler and Pratt (2016).

Taxon 5528.5: The White-breasted Waterhen Amaurornis phoenicurus of Car Nicobar Island, described as Amaurornis phoenicurus leucocephalus Abdulali, 1964, was long unrecognized. Praveen and Khot (2023) have shown on the basis of examination of more material than was available earlier that Amaurornis phoenicurus leucocephala should be recognized.

Taxon 6165: The form of Dunlin Calidris alpina breeding in central to eastern Russia, Calidris alpina centralis is now recognized as subspecifically distinct, in alignment with other major checklists.

Taxa 6622–6627: Despite the recent description of a new subspecies of Little Tern Sterna albifrons levantinus Kiat et al., 2023, this taxon is not yet recognized by Clements et al. (2023) pending resolution of its distinctions from the previously described race praetermissa (Baker, 1928) for which the holotype is from the same collector, region (Persian Gulf), and time period as a paratype of levantinus. Baker’s (1928) praetermissa has long been synonymized with S. a. innominata (Zarudny and Loudon, 1902).

Taxa 7054–7055: A new cryptic subspecies of Manx Shearwater Puffinus puffinus known to breed only in the Canary Islands and possibly Madeira has been characterized on the basis of morphology, genetics, vocalizations, and breeding chronology (Rodríguez et al. 2020). The name of the new subspecies is Puffinus puffinus canariensis Rodríguez et al., 2020.

Taxon 8152: The southwestern U.S. and Mexican subspecies of the Northern Goshawk Accipiter gentilis (now American Goshawk A. atricapillus; Chesser et al. 2023), Accipiter atricapillus apache van Rossem, 1938 is now recognized as a valid subspecies based on detailed studies by Hubbard (2008) and the high proportion of unique haplotypes in that population indicative of long isolation (Bayard de Volo et al. 2013).

Taxa 8186.3–8186.6: The White-tailed Eagle Haliaeetus albicilla of Greenland, named Haliaeetus albicilla groenlandicus Brehm, 1831, is somewhat larger than elsewhere (Vaurie 1965) and, being broadly allopatric, is not strictly clinal, so we recognize this subspecies.

Taxa 9116–9120, 9123–9130: The Kai Besar (Great Kei) Island subspecies Ninox novaeseelandiae remigialis Stresemann, 1930 was described from a single molting immature specimen (Stresemann 1930). Recordings show this taxon to be vocally very like Barking Owl Ninox connivens and it is thus realigned from Ninox boobook remigialis to Ninox connivens remigialis (J. Eaton in litt. 2023).

Taxa 10341–10342: Formerly treated as a group within Green Barbet, Stactolaema (now Cryptolybia) olivacea belcheri/rungweensis, these two forms were considered to be in different groups treated as separate species by Clancey (1989). A recent phylogeny places them (but with uncertainty) in different clades (Fjeldså and Bowie 2021). Hence Clements et al. (2023) now considers them to be monotypic groups, as Cryptolybia olivacea belcheri and Cryptolybia olivacea rungweensis.

Taxa 10405–10406: A new subspecies of the Yellow-spotted Barbet Buccanodon duchaillui is recognized, as Buccanodon duchaillui dowsetti Boesman and Collar, 2019. Although vocal differences are marked and dowsetti was originally described as a full species (HBW and BirdLife International 2022), morphological differences have proven elusive (Boesman and Collar 2019), and the WGAC and Clements et al. (2023) decision is to treat these as subspecies.

Taxa 10866–10867: The Ochraceous Piculet Picumnus limae, into which P. fulvescens was subsumed based on Lima et al. (2020) and https://www.museum.lsu.edu/~Remsen/SACCprop845.htm, is now treated as comprising two subspecies that intergrade widely: the dark-plumaged Picumnus limae fulvescensand the pale Picumnus limae limae.

Taxa 11124.3–11124.6: The Darjeeling Woodpecker Dendrocopos darjellensis is now treated as having two subspecies: Dendrocopos darjellensis darjellensis of the eastern Himalayas and Dendrocopos darjellensis desmursi of mountains of China, based on the noticeably longer bills of Himalayan birds (Vaurie 1965, Wolters 1976). This difference has been stated to be probably clinal, and the subspecies desmursi was thus unrecognized by e.g., Winkler et al. (1995). The possibility that there is character displacement in bill length between the former Crimson-breasted Woodpecker D. cathpharius/pernyii (now two species) and the two subspecies of D. darjellensis should be examined; cathpharius and darjellensis occur sympatrically in the Himalayas, while pernyii and desmursi overlap much less in China.

Taxon 11516.5: The subspecies of Great Slaty Woodpecker Mulleripicus pulverulentus mohun Ripley, 1950 is recognized based on prior examination of specimens (Rasmussen and Anderton 2005), in agreement with the description of M. p. harteri (Hesse 1911), and is in alignment with Gill et al. (2023) and Dickinson and Remsen (2013).

Taxa 12225–12227: The extinct Lord Howe Island subspecies of Norfolk Island Parakeet Cyanoramphus cookii subflavescens is added.

Taxon 13069.3: The subspecies named from Obi of the North Moluccan Pitta Erythropitta rufiventris, Erythropitta rufiventris obiensis Hachisuka, 1935 is recognized based on its slightly lighter blue breast and its acceptance by Eaton et al. (2021).

Taxon 13996: The Bicolored Antpitta Grallaria rufocinerea has been shown to be monotypic, as analysis (Cuervo 2022) of the holotype of Grallaria r. rufocinerea Hernández-Camacho and Rodríguez, 1979 revealed that the throat color, the putative distinguishing feature between the taxa, does not differ and the apparent difference was due to feather bases showing through.

Taxon 14973: The northern Central American subspecies Buff-throated Foliage-gleaner (amusos) Automolus ochrolaemus amusos Peters, 1929 is synonymized with Fawn-throated Foliage-gleaner (Mexican) Automolus cervinigularis cervinigularis (Sclater, 1857), following Dickinson and Christidis (2014) and Gill et al. (2023).

Taxon 15029: A newly described form of rayadito from the Diego Ramirez Islands, named the Subantarctic Rayadito Aphrastura subantarctica Rozzi et al., 2022, is larger but shorter-tailed than the mainland Aphrastura spinicauda, and nests in tunnels rather than tree holes (Rozzi et al. 2022). While tentatively considered by Clements et al. (2023) and Gill et al. (2023) to be a subspecies of Thorn-tailed RayaditoAphrastura spinicauda, as Aphrastura spinicauda subantarctica based on its seemingly identical plumage, a lack of information on any vocal differences, and degree of genetic divergence, further study may bolster the case for species status for subantarctica.

Taxon 15131: The subspecies Asthenes wyatti brunnescens Nores and Yzurieta, 1983 of Streak-backed Canastero is now recognized, in alignment with other global lists (Dickinson and Christidis 2014, HBW and BirdLife International 2022, and Gill et al. 2023).

Taxon 15759: The Black-and-white Becard Pachyramphus albogriseus is now considered comprised of just two subspecies, Pachyramphus a. albogriseus and Pachyramphus a. ornatus. Pachyramphus albogriseus coronatus Phelps and Phelps Jr., 1953 of the Santa Marta Mountains and northern Venezuela is considered undiagnosable and a synonym of the nominate (Musher et al. 2023).

Taxon 15763: The Cryptic Becard Pachyramphus salvini is now monotypic, as taxon guayaquilensis Zimmer, 1936 is considered undiagnosable and a synonym of salvini (Musher et al. 2023).

Taxon 16161: Described to science as a new phylogenetic species, Western Olivaceous Flatbill Rhynchocyclus aequinoctialis cryptus Simões et al., 2021 of southwestern Amazonian Brazil evidently lacks diagnostic phenotypic characters but is genetically and vocally divergent from other taxa, and is broadly sympatric with Eastern Olivaceous Flatbill Rhynchocyclus olivaceus (Simões et al. 2021). While treated by WGAC and Clements et al. (2023) as a subspecies, further study may well lead to its treatment as a full biological species.

Taxon 18299: Rosy Minivet Pericrocotus roseus is considered monotypic, as Pericrocotus roseus stanfordi Vaughan and Jones, 1913 is a highly variable hybrid. Clements et al. (2023) now align with e.g., Gill et al. (2023) and HBW and BirdLife International (2022).

Taxon 20066.5: The form ofAshy Drongo Dicrurus leucophaeus of Simeulue Island originally described as Dicrurus leucophaeus celaenus Oberholser, 1912 is reinstated to Clements et al. (2023). This form had been in synonymy in the Clements taxonomy with D. l. periophthalmicus (Salvadori, 1895) of the Mentawai Islands since at least Clements (2007); however, it was described as similar to Javan cineraceus but darker, especially below. Based on plumage celaenus and periophthalmicus fall into different groups that might be specifically distinct. Recognition of celaenus is in alignment with Gill et al. (2023) and Eaton et al. (2016).

Taxon 20873.5: The form of Plush-crested Jay Cyanocorax chrysops from northeastern Brazil south of the Amazon, Cyanocorax chrysops insperatus Pinto and Camargo, 1961, is diagnosable based on a large series (Kirwan in litt., 2023) and is hence restored to Clements et al. (2023). Santos et al. (2011) considered birds from the Serra do Cachimbo, Para, Brazil, to be closer to C. cyanopogon, but specimens from the type locality are chrysops-type (Kirwan in litt., 2023), and thus insperatus is maintained within the latter species.

Taxa 21585–21585.5: Two subspecies of Coal Tit Periparus ater (Eck, 1998), Periparus ater martensi and Periparus ater eckodedicatus (Martens et al., 2006) are added to Clements et al. (2023), based on Pentzold et al. (2013) and in alignment with e.g., Gill et al. (2023).

Taxa 21985.3–21985.6: The Rufous-tailed Lark Ammomanes phoenicura shows marked variation in depth of plumage coloration, and was treated as polytypic in Rasmussen and Anderton (2005). Although plumage color variation may be shown to be clinal, Clements et al. (2023) recognizes the southwestern Indian population as Ammomanes phoenicura testacea, aligning with Gill et al. (2023).

Taxa 22287–22291: The subspecies of Asian Short-toed Lark Alaudala cheleensis are modified; Alaudala cheleensis kukunorensis is deleted, while Alaudala cheleensis seebohmi Sharpe, 1890 is added (Alström, in litt. 2023).

Taxa 22302–22304: The Sand Lark Alaudala raytal now has just two recognized subspecies, with the synonymy of Alaudala raytal krishnakumarsinhji into Alaudala raytal adamsi, following Ganpule and Alström (2023).

Taxa 22349–22358: The Oriental Skylark Alauda gulgula subspecies Alauda gulgula australis Brooks, 1873 of southwestern India is now recognized, as in Rasmussen and Anderton (2005), although its very saturated plumage may be interpreted as clinal. The sequence of subspecies is modified in accordance with geographical convention.

Taxa 22784–22786: The White-browed Tailorbird Orthotomus nigriceps has been shown to be polytypic (Halley 2022), and the newly described subspecies Orthotomus nigriceps luminosus            Halley, 2022 is now recognized by Clements et al. (2023), in alignment with Gill et al. (2023).

Taxa 24146–24148: The subspecies of Yellowish Bulbul Hypsipetes everetti samarensis Rand and Rabor, 1959 from Samar and Leyte is synonymized with Hypsipetes everetti everetti following Parkes (1973) and in alignment with other checklists.

Taxa 24232–24234: The Ruby-throated Bulbul Rubigula dispar has been shown to differ in iris color between islands, with Javan and Bali birds having yellow irides, while Sumatran birds have reddish irides (Berryman and Collar 2023). This, with additional mensural differences, led to the description of a new subspecies, Rubigula dispar matamerah Berryman and Collar, 2023 for the Sumatran population, now added to Clements et al. (2023).

Taxa 24817–24819: The Black-throated Tit (Red-headed group) Aegithalos concinnus iredalei/rubricapillus is no longer considered monotypic, with the recognition of Aegithalos concinnus rubricapillus (Ticehurst, 1925), as suggested by Päckert et al. (2010) and in alignment with Rasmussen and Anderton (2012), HBW and BirdLife International (2022), and Gill et al. (2023).

Taxa 25659–25661: The Gray-throated Babbler Stachyris nigriceps coei Ripley, 1952 is synonymized with the nominate Stachyris nigriceps nigricepsBlyth, 1844, as suggested by Ripley (1980) and in alignment with Gill et al. (2023). Ripley (1980) also suggested synonymizing his Stachyris nigriceps spadix Ripley, 1948 with Stachyris nigriceps coltarti Harington, 1913, but this has not been widely adopted, and the genomic data of Lim et al. (2020) suggest the validity of spadix.

Taxa 25972–25976: The Striated Laughingthrush Grammatoptila striata was long placed in the broad genus Garrulax, during which period the name austeni Oates, 1889 was replaced by brahmaputra Hachisuka, 1953, but because brahmaputra was replaced before 1961 and is still in use, austeni is permanently invalid so brahmaputra must be used (ICZN 59.3), if it represents a valid taxon. Although putative plumage distinctions of brahmaputra may not hold, ML images show that the iris color appears to be darker (redder or browner) from that of Yunnan cranbrooki, in which it is paler and yellower, and thus Clements et al. (2023) now recognizes Grammatoptila striata brahmaputra.

Taxa 28042–28051.5: A new subspecies of thrush from the Cauca Valley of Colombia (Avendaño et al. 2021) is tentatively assigned to Clay-colored Thrush Turdus grayi, as Turdus grayi suareziAvendaño et al., 2021.

Taxon 28243: The New Ireland form of the Island Thrush Turdus poliocephalus, Turdus poliocephalus beehleri Ripley, 1977 is now recognized by Clements et al. (2023), in alignment with Gill et al. (2023), Gregory (2017), and others. The geographically nearest subspecies at the time of description of beehleri was heinrothi Rothschild and Hartert, 1924 from Mussau (St. Matthias), far to the northeast of eastern New Ireland. An undescribed or indeterminate form is also now known from the mountains of New Britain (Dutson 2011, Gregory 2017).

Taxa 28301–23805: Asian Brown Flycatcher Muscicapa dauurica was treated as monotypic in Clements (2007), and more recently as comprising two subspecies, M. d. dauurica breeding across much of northeastern Asia, and M. d. siamensis, breeding in southeast Asia. However, the breeding population of South Asia, M. d. poonensis, was omitted from earlier versions of Clements through Clements et al. (2022). Muscicapa dauurica poonensis is thus now added to Clements et al. (2023).

Taxa 28987–28987.6: The Himalayan Bluetail Tarsiger rufilatus has been shown to be polytypic, and hence the western Himalayan form Tarsiger rufilatus pallidior (Baker, ECS, 1924) is now recognized (Wei et al. 2022b).

Taxa 30975–30977: The western Himalayas subspecies of Robin Accentor Prunella rubeculoides murariaMeinertzhagen and Meinertzhagen, 1969 is recognized in Clements et al. (2023), based on specimens examined for Rasmussen and Anderton (2005). The type specimen was collected by Biddulph, and is thus doubtless of genuine provenance. However, muraria was synonymized by Ripley (1961), who considered the species monotypic, and Vaurie (1972) did not mention geographic variation in the large Tibet series he examined. Cheng (1987) implicitly recognized muraria (extralimital to the region) by treating P. rubeculoides as polytypic while explicitly considering fusca Mayr, 1937 and beicki Mayr, 1937 synonyms of the nominate. Clements (2007) recognized fusca but not muraria and included Xinjiang in the range of fusca, but this seems geographically unlikely.

Taxa 30122–30126: Arachnothera everetti pars Riley, 1939, was synonymized with A. everetti (Sharpe, 1893) by del Hoyo and Collar (2016). It was treated as A. modesta pars (Clements 2007), but was not recognized by e.g., Gill et al. (2023) and earlier versions. Based on geographical location and reexamination of specimens, WGAC and Clements et al. (2023) agree with the synonymy of pars into a monotypic Arachnothera everetti.

Taxa 31444–31448: Svensson (2015) showed that Cyrenaican (east Libyan) chaffinches differ from other populations to a degree indicative of subspecies status. This taxon is now African Chaffinch Fringilla spodiogenys harterti Svensson, 2015. Clements et al. (2023) now recognizes this form, in accord with Shirihai and Svensson (2018) and Gill et al. (2023).

Taxa 35204–35206, 35217: The subspecies darwini of remote Isla Darwin, northwestern Galapagos Islands, is moved from Genovesa Cactus-Finch Geospiza propinqua to Large Ground-Finch Geospiza magnirostris, as Geospiza magnirostris darwini, as proposed by del Hoyo and Collar (2016), and aligning with Gill et al. (2023). Bill size is bimodal (Grant 1986), so much so that darwini has at times been considered two different species (G. conirostris and G. magnirostris), but in all individuals the curvature of the beak sides and base of the lower mandible resembles G. magnirostris (Grant 1986). Geographically, the widespread G. magnirostris seems a much more likely candidate for a source population for the birds of the far-flung Isla Darwin than the highly isolated Genovesa species G. propinqua.

Changes to Groups

Taxa 414–416: A small percentage of steamer-ducks Tachyeres sp. on the Falkland Islands are flighted, but at least some of these flying individuals have been shown to be Falkland Steamer-Duck Tachyeres brachypterus (Fulton et al. 2012, Campagna et al. 2019). Thus, two groups are now recognized within the species: Falkland Steamer-Duck (Flightless) Tachyeres brachypterus (Flightless) and Falkland Steamer-Duck (Flying) Tachyeres brachypterus (Flying).

Taxon 1118: An evidently undescribed form of wood-quail has been documented in the east slope of the Andes of central Peru. This is now treated here as Pasco Wood-Quail (undescribed form) Odontophorus [undescribed form].

Taxa 1920–1922: The two subspecies of Delegorgue’s Pigeon Columba delegorguei are identifiable except perhaps in a zone of intergradation in Malawi (del Hoyo and Collar 2014), and hence are now treated as two groups, Delegorgue’s Pigeon (Northern) Columba delegorguei sharpei of eastern Africa and Delegorgue’s Pigeon (Southern) Columba delegorguei delegorguei, occurring from Malawi to South Africa.       

Taxa 3363–3370: A revision of the Brush Cuckoo Cacomantis variolosus complex (Wu et al. 2022) has led to the recognition that there is an evidently undescribed form of Cacomantis on the Tanimbar Islands that is now treated here as Brush Cuckoo (Tanimbar) Cacomantis variolosus [undescribed form]. In addition, new groups recognized in the complex are: Brush Cuckoo (Sulawesi) Cacomantis variolosus virescens, of Sulawesi and some nearby islands; Brush Cuckoo (Solomons) Cacomantis variolosus addendus, of the Solomon Islands; and Brush Cuckoo (Manus) Cacomantis variolosus blandus of Manus Island in the Admiralty Islands, western Bismarck Archipelago.

Taxa 3479–3485: An integrative revision of the eared-nightjars of the Lyncornis macrotis complex (Sangster et al. 2022) has led to treatment of L. macrotis as comprising four widely disjunct groups: Great Eared-Nightjar (Great) Lyncornis macrotis cerviniceps/bourdilloni, in southwestern India and northeastern India through Southeast Asia including northern Malaysia; Great Eared-Nightjar (Simeulue, misspelled Simelue) Lyncornis macrotis jacobsoni, isolated on Simeulue Island, off northwestern Sumatra; Great Eared-Nightjar (Philippine) Lyncornis macrotis macrotis, of the Philippines (except the West Visayas and the Palawan group); and Great Eared-Nightjar (Sulawesi) Lyncornis macrotis macropterus of the Sulawesi region.

Taxa 3723–3733: A recent study of the vocalizations of the Savanna Nightjar (Sangster et al. 2021) concluded that the differences between taxon groups are indicative of three separate species. WGAC and Clements et al. (2023) have now split the Chirruping Nightjar C. griseatus of the Philippines, but consider the potential split of the monticolus group less robust and requiring further study. Thus, two groups are now recognized: the mainly Asian continental Savanna Nightjar (Northern) Caprimulgus affinis [monticolus Group], with three subspecies, and the mainly Indonesian Savanna Nightjar (Sunda) Caprimulgus affinis [affinis Group], with five subspecies.

Taxa 3896–3898: The White-throated Needletail Hirundapus caudacutus is comprised of two species groups that are often field-identifiable (Rasmussen and Anderton 2005, Robson 2005, Eaton et al. 2021) and candidate species splits (limbo-split in e.g., Treesucon and Limparungpatthanakij 2018, Puan et al. 2020, Craik and Minh 2018), now treated here as: White-throated Needletail (White-lored) Hirundapus caudacutus caudacutus, which breeds in north-central to northeastern Asia, and White-throated Needletail (Himalayan) Hirundapus caudacutus nudipes, which breeds from the Himalayas through mountains of China. Although nudipes was long thought to be resident (Chantler and Driessens 1995), both taxa have now been documented in Southeast Asia (Treesucon and Limparungpatthanakij 2018, Puan et al. 2020, Craik and Minh 2018).

Taxa 6743–6747: The long-standing treatment of the Sunbittern Eurypyga helias as a single species has recently come into question due to plumage and vocal differences (e.g., Howell and Dyer 2022, Dyer and Howell 2023). Pending reevaluation of species limits, they are thus now treated as two groups, Sunbittern (Northern) Eurypyga helias major/meridionalis and Sunbittern (Amazonian) Eurypyga helias helias.

Taxa 6819–6821: With the break-up of the Wandering Albatross group, the status of gibsoni Robertson and Warham, 1992, which breeds on Adams Island, Auckland Islands, must be addressed. Although Robertson and Nunn (1998) proposed it be recognized as a full species, Diomedea gibsoni, and this was widely followed, supporting data for that treatment were not provided. A near lack of genetic differentiation between gibsoni of Adams Island, Auckland Islands and antipodensis mainly of Antipodes Islands (Alderman et al. 2005) have led to their being considered conspecific, although gibsoni more closely resembles and is sometimes treated as a subspecies of exulans (Harrison et al. 2021). Thus, Clements et al. (2023) now recognizes two groups within Antipodean Albatross Diomedea antipodensis, Antipodean Albatross (New Zealand) Diomedea antipodensis antipodensis and Antipodean Albatross (Gibson’s) Diomedea antipodensis gibsoni.

Taxa 6879–6881: The taxa of Black-bellied Storm-Petrel Fregetta tropica fall into two clades (Robertson et al. 2016), a subantarctic clade that has a black belly stripe, and the form melanoleuca of Gough Island and Tristan da Cunha in the South Atlantic that has a pure white belly (Howell and Zufelt 2019). These are thus now two groups: Black-bellied Storm-Petrel (Subantarctic) Fregetta tropica tropicaand Black-bellied Storm-Petrel (Gough) Fregetta tropica melanoleuca.

Taxon 7628: A putatively undescribed form of Turkey Vulture Cathartes aura is here included as Turkey Vulture (Choco) Cathartes aura [undescribed form].

Taxa 7688–7696: The groups of Oriental Honey-buzzard Pernis ptilorhynchus are modified to divide the Oriental Honey-buzzard (Indomalayan) Pernis ptilorhynchus [ptilorhynchus Group] (as recognized by Clements et al. 2022) into the Oriental Honey-buzzard (Indomalayan) Pernis ptilorhynchus ruficollis/philippensisgroup occurring from South and Southeast Asia through the Philippines (except the Palawan group) and the Oriental Honey-buzzard (Sunda) Pernis ptilorhynchus [ptilorhynchus Group] of southern Indochina through the Greater Sundas and the Palawan group, as suggested in Eaton et al. (2016). 

Taxon 8639: With the split of Choco Screech-Owl Megascops centralis (Chesser et al. 2019), it has become clear that the vocalizations of the screech-owls of lowland western Costa Rica are atypical for any known taxon (Howell and Dyer 2022, Dyer and Howell 2023, where called “Skutch’s Vermiculated Screech-Owl”). This putatively undescribed taxon is now added, as Puntarenas Screech-Owl (undescribed form) Megascops [undescribed form].

Taxa 9355–9357: With the four-way split of Black-throated Trogon Trogon rufus (https://www.museum.lsu.edu/~Remsen/SACCprop921.htm), the newly described Trogon muriciensis Dickens et al., 2021 is now considered a subspecies of Atlantic Black-throated Trogon Trogon chrysochloros. Hence, this species is now treated as comprising two groups:  Atlantic Black-throated Trogon (Alagoas) Trogon chrysochloros muriciensis, restricted as far as known to the Murici Forest of Alagoas, Brazil, and the widespread Atlantic Black-throated Trogon (Southern) Trogon chrysochloros chrysochloros, occurring from southeastern Brazil through eastern Paraguay and northeastern Argentina.

Taxa 9629–9638: The Lesser Sundas Common Kingfisher subspecies Alcedo atthis floresiana Sharpe, 1892 was originally described as similar to Eurasian A. a. ispida but somewhat intermediate to hispidoides (Sharpe 1892), with partially chestnut ear coverts; thus floresiana was earlier placed in the atthis group. However, with its darker blue plumage and reduced chestnut on ear coverts Alcedo atthis floresiana is now deemed a member of the hispidoides group.

Taxa 9731–9735: The African Pygmy Kingfisher Ispidina picta is now treated as two groups: African Pygmy Kingfisher (Northern) Ispidina picta picta/ferrugina, which lacks blue above the white neck-sides mark and occurs over most of tropical Africa, including Pemba Island, Tanzania; and the somewhat migratory monotypic African Pygmy Kingfisher (Southern) Ispidina picta natalensis, in which a blue spot is present, and primarily occurs in southern Africa north to central Tanzania, possibly including Pemba (del Hoyo and Collar 2014).

Taxa 10479–10490: Red facial feathering appears to have evolved independently in two lineages of Coppersmith Barbet Psilopogon haemacephalus (den Tex and Leonard 2013, Lim et al. 2015), in Java and Bali and in the Philippines, where some populations have varying amounts of red facial feathering. New groups are created thus: Coppersmith Barbet (Western Yellow-faced) Psilopogon haemacephalus indicus/delicusfor taxa of (mainly) continental Asia and Sumatra; Coppersmith Barbet (Javan Red-faced) Psilopogon haemacephalus roseus, Java and Bali; Coppersmith Barbet (Philippine Yellow-faced) Psilopogon haemacephalus [haemacephalus Group] for most of the Philippines taxa (except those of the West Visayas); and Coppersmith Barbet (Philippine Red-faced) Psilopogon haemacephalus [intermedius Group], of the West Visayas, west-central Philippines.

Taxa 12225–12227: With the addition of the extinct Lord Howe Island subspecies, the following groups are created for the Norfolk Island Parakeet Cyanoramphus cookii: Norfolk Island Parakeet (Norfolk I.) Cyanoramphus cookii cookii of Norfolk Island, and Norfolk Island Parakeet (Lord Howe I.) Cyanoramphus cookii subflavescens, extinct from Lord Howe Island sometime after 1869 (Greenway 1958).

Taxa 12285–12289: With the split of Orange-breasted Fig-Parrot Cyclopsitta gulielmitertii, the pre-existing group Black-fronted Fig-Parrot (Black-fronted) Cyclopsitta gulielmitertii nigrifrons of northern New Guinea becomes Black-fronted Fig-Parrot (Black-fronted) Cyclopsitta nigrifrons nigrifrons, while the pre-existing group Black-fronted Fig-Parrot (Creamy-breasted) Cyclopsitta gulielmitertii amabilis/ramuensis of northeastern New Guinea becomes Black-fronted Fig-Parrot (Creamy-breasted) Cyclopsitta nigrifrons amabilis/ramuensis.

Taxa 12517–12521: The allocation of the Gray Parrot of Príncipe Island, Psittacus princeps Alexander, 1909, varies between authorities, some sequenced individuals being closer on mtDNA to Psittacus timneh but others embedded within erithacus, suggesting that erithacus may be a later arrival to Príncipe (Melo and O’Ryan 2007, Gill et al. 2023). It is placed with P. erithacus as Psittacus erithacus princeps in Clements et al. (2023) but Alexander described it as darker, almost blackish-gray and larger than the nominate (Alexander 1909); this clearly requires further study.

Taxa 13076–13081: Reflecting genetic and morphological evidence (Irestedt et al. 2013, del Hoyo and Collar 2016), two groups are recognized for the South Papuan Pitta Erythropitta macklotii, as follows: South Papuan Pitta (Western) Erythropitta macklotii [macklotii Group] of most of western and southern New Guinea, associated islands, and northernmost Australia; and the monotypic South Papuan Pitta (D’Entrecasteaux) Erythropitta macklotii finschii of the D’Entrecasteaux Islands. The subspecies found in southeastern New Guinea, loriae, may be best treated within the finschii group, however.

Taxa 13135–13151: With the breakup of the Hooded Pitta Pitta sordida, pre-existing group names and species allocations in the complex change to some extent. For the Western Hooded Pitta P. sordida, these are now Western Hooded Pitta (Chestnut-crowned) Pitta sordida cucullatafor the brown-capped continental Asian taxon; Western Hooded Pitta (Sunda) Pitta sordida mulleri/bangkanafor the black-capped Sundaic birds and bangkana of the Bangka and Belitung islands east of southern Sumatra, in which the crown feathers are typically intermixed brown and black; Western Hooded Pitta (Philippine) Pitta sordida sordida/palawanensis of the Philippines; and Western Hooded Pitta (Sangihe) Pitta sordida sanghirana of Sangihe (north of Sulawesi).

For the Eastern Hooded Pitta Pitta novaeguineae, the groups are now Eastern Hooded Pitta (Papuan) Pitta novaeguineae novaeguineae/goodfellowiof most of New Guinea and associated islands, and Eastern Hooded Pitta (Numfor) Pitta novaeguineae mefoorana of Numfor Island, Geelvink Bay.

Taxa 14216–14217: The Black-headed Antthrush Formicarius nigricapillus is comprised of two plumage and vocal groups (Howell and Dyer 2022, Dyer and Howell 2023), now represented by the following groups: Black-headed Antthrush (Central American) Formicarius nigricapillus nigricapillus of the mountains of Costa Rica and Panama; and Black-headed Antthrush (Choco) Formicarius nigricapillus destructus, found in the Chocó region of western Colombia and Ecuador.

Taxa 14278–14286: The voice of the Gray-throated Leaftosser Sclerurus albigularis varies markedly geographically (Howell and Dyer 2022, Dyer and Howell 2023), and the complex may involve multiple species. Two groups are introduced here: the monotypic Gray-throated Leaftosser (Central American) Sclerurus albigularis canigularis of the mountains of Costa Rica and western Panama, and the polytypic Gray-throated Leaftosser (South American) Sclerurus albigularis [albigularis Group], widespread in South America, mainly in the Andes and outlying ranges.

Taxa 14623–14626: With the split of the Curve-billed Scythebill Campylorhamphus procurvoides, pre-existing group names and species allocations of the groups within the newly defined species Tapajos Scythebill (Rondonia) Campylorhamphus probatus are altered thus:  Curve-billed Scythebill (Rondonia) Campylorhamphus procurvoides probatus becomes Tapajos Scythebill (Rondonia) Campylorhamphus probatus probatus, and Curve-billed Scythebill (Tapajos) Campylorhamphus procurvoides cardosoi becomes Tapajos Scythebill (Tapajos) Campylorhamphus probatus cardosoi.         .

Taxa 14972–14974: With the split of the Fawn-throated Foliage-gleaner Automolus cervinigularis from Buff-throated Foliage-gleaner Automolus ochrolaemus, pre-existing group names and species allocations of the groups within the newly defined species change thus: Buff-throated Foliage-gleaner (Mexican) Automolus ochrolaemus cervinigularis of southern Mexico to Honduras becomes Fawn-throated Foliage-gleaner (Mexican) Automolus cervinigularis cervinigularis and Buff-throated Foliage-gleaner (hypophaeus) Automolus ochrolaemus hypophaeus of east Nicaragua to Panama becomes Fawn-throated Foliage-gleaner (hypophaeus) Automolus cervinigularis hypophaeus.

Taxa 14976–14980: With the split of the Fawn-throated Foliage-gleaner Automolus cervinigularis from Buff-throated Foliage-gleaner Automolus ochrolaemus, the name of the latter changes to Ochre-throated Foliage-gleaner, so pre-existing group names and species allocations of the groups within the newly defined species are changed as follows: Buff-throated Foliage-gleaner (pallidigularis) becomes Ochre-throated Foliage-gleaner (pallidigularis); Buff-throated Foliage-gleaner (turdinus) becomes Ochre-throated Foliage-gleaner (turdinus); Buff-throated Foliage-gleaner (ochrolaemus) becomes Ochre-throated Foliage-gleaner (ochrolaemus); and Buff-throated Foliage-gleaner (auricularis) becomes Ochre-throated Foliage-gleaner (auricularis).

Taxa 15048–15052: Two allopatric, rather dissimilarly plumaged allopatric groups are now recognized for the Streaked Tit-Spinetail Leptasthenura striata: Streaked Tit-Spinetail (Streak-throated) Leptasthenura striata striata/superciliaris, occurring along the western Andes of Peru into far northwestern Chile; and Streaked Tit-Spinetail (White-throated) Leptasthenura striata albigularisfrom dry intermontane valleys of Peru from at least Junín to Ayacucho.

Taxa 17859–17867: Based on recent research (e.g., Joseph et al. 2021), a new group is added to the Helmeted Friarbird Philemon buceroides complex, Helmeted Friarbird (Arnhem Land) Philemon buceroides gordoni/ammitophilus of north Australia (Northern Territory), and thus the former Helmeted Friarbird (Helmeted) Philemon buceroides [buceroides Group] becomes Helmeted Friarbird (Tenggara) Philemon buceroides buceroides/neglectus, now restricted to the Lesser Sundas.

Taxa 18386–18402: Bar-bellied Cuckooshrike (Roving) Coracina striata [sumatrensis Group] is added as a new group (polytypic). Subspecies from the Sundaic region are placed in this group, while the Bar-bellied Cuckooshrike (Philippine) Coracina striata [striata Group] is now limited to Philippine taxa.

Taxa 18410–18417: Two groups are now recognized within the Wallacean Cuckooshrike Coracina personata, the Wallacean Cuckooshrike (Wallacean) Coracina personata [personata Group], widespread within Wallacea, and the Wallacean Cuckooshrike (Alor) Coracina personata alfredianaof Lomblen and Alor, east-central Lesser Sundas, the latter considered a separate species by Eaton et al. (2016).

Taxa 19671–19677: Two groups are now recognized for the Black-backed Puffback Dryoscopus cubla, Black-backed Puffback (Black-winged) Dryoscopus cubla affinis of coastal Somalia to Tanzania, and Black-backed Puffback (White-winged) Dryoscopus cubla [cubla Group] of inland eastern and southern Africa. The two groups intergrade, mainly inland from the east African coast (del Hoyo and Collar 2016).

Taxa 19961–19980: With the split of Rufous Fantail Rhipidura rufifrons, pre-existing group names and species allocations of the groups within the newly defined species are changed as follows:

• For the Santa Cruz Fantail Rhipidura melaenolaema, the Rufous Fantail (White-fronted) Rhipidura rufifrons melaenolaema/utupuae becomes Santa Cruz Fantail (White-fronted) Rhipidura melaenolaema melaenolaema/utupuae of Vanikoro and Utupua, respectively, and Rufous Fantail (Brown-capped) Rhipidura rufifrons agilis becomes Santa Cruz Fantail (Brown-fronted) Rhipidura melaenolaema agilis of Nendo (all from the Santa Cruz Islands, southeastern Solomon Islands).    
• For the Micronesian Rufous Fantail Rhipidura versicolor, the extinct Rufous Fantail (Guam) Rhipidura rufifrons uraniae becomes Micronesian Rufous Fantail (Guam) Rhipidura versicolor uraniae; Rufous Fantail (Marianas) Rhipidura rufifrons saipanensis/mariae becomes Micronesian Rufous Fantail (Marianas) Rhipidura versicolor saipanensis/mariae of the Marianas Islands (except Guam); and Rufous Fantail (Yap) Rhipidura rufifrons versicolor becomes Micronesian Rufous Fantail (Yap) Rhipidura versicolor versicolor, of Yap, Caroline Islands.
• For the Solomons Rufous Fantail Rhipidura rufofronta, the Rufous Fantail (Brown-backed) Rhipidura rufifrons [rufofronta Group] becomes Solomons Rufous Fantail (Brown-backed) Rhipidura rufofronta [rufofronta Group]; the Rufous Fantail (Rufous-backed) Rhipidura rufifrons russata/kuperi becomes Solomons Rufous Fantail (Rufous-backed) Rhipidura rufofronta russata/kuperi; and the Rufous Fantail (Dark-throated) Rhipidura rufifrons ugiensis becomes Solomons Rufous Fantail (Dark-throated) Rhipidura rufofronta ugiensis.

Taxa 20059–20079: Groups within the Ashy Drongo Dicrurus leucophaeus complex are modified such that the former Ashy Drongo (Chinese White-faced) Dicrurus leucophaeus [innexus Group] is broken up into three groups: Ashy Drongo (White-cheeked) Dicrurus leucophaeus leucogenis, breeding in northeastern Asia; Ashy Drongo (White-lored) Dicrurus leucophaeus salangensis, which breeds in southeastern China; and Ashy Drongo (Hainan) Dicrurus leucophaeus innexus, of Hainan Island, off southeastern China.

Taxa 20095–20099, 20122: Sumatran Drongo Dicrurus sumatranus no longer includes the Mentawai Islands subspecies viridinitens (Salvadori, 1895), and is now monotypic. Hair-crested Drongo Dicrurus hottentottus now includes viridinitens, as Hair-crested Drongo (Mentawai) Dicrurus hottentottus viridinitens. Dicrurus viridinitens was treated by Eaton et al. (2016) as a full species, as with several other taxa currently in D. hottentottus.

Taxa 20113–20115: For the newly split Palawan Drongo Dicrurus palawanensis, two groups are created: these are Palawan Drongo (Palawan) Dicrurus palawanensis palawanensis of the Palawan group of islands, and Palawan Drongo (Cuyo) Dicrurus palawanensis cuyensis; however, the affinities of cuyensis of small islands between the Palawan group and Mindoro (southwestern Philippines) are far from clear, and cuyensis was “limbo-split” by Allen (2020).

Taxa 20332–20335: New groups are created for the Black Paradise-Flycatcher Terpsiphone atrocaudata. These are Black Paradise-Flycatcher (Northern) Terpsiphone atrocaudata atrocaudata/illex (though in the group entry misspelled ilex), the breeding forms from South Korea and Japan including the Ryukyu Islands, and Black Paradise-Flycatcher (Philippines) Terpsiphone atrocaudata periophthalmica, which breeds in Lanyu Island, Taiwan, and the Batanes Islands of the far northern Philippines. The form T. a. illex that breeds on the Ryukyu Islands was limbo-split by Chikara (2019) and called Ryukyu Paradise-Flycatcher, but atrocaudata and illex are closely related sister taxa (Fabre et al. 2012).

Taxa 20879–20898: The groups and names thereof within Steller’s Jay Cyanocitta stelleri have been modified slightly on the basis of new information (Cicero et al. 2022). The group Steller’s Jay (Northwest Interior) Cyanocitta stelleri annectensof interior British Columbia to northeastern Oregon and northwestern Wyoming is added. The English group name of Steller’s Jay (Interior) is changed to Steller’s Jay (Southwest Interior), and that of Steller’s Jay (Central American) is changed to Steller’s Jay (Middle American).

Taxa 21138–21141: A second new group within Slender-billed Crow Corvus enca is created for the Slender-billed Crow (Sulawesi) Corvus enca celebensis/mangoli, with subspecies Corvus enca celebensis from the Sulawesi region except Sula Islands (Banggai Island form probably this); and Corvus enca mangoli of the Sula Islands.

Taxon 23163:  An evidently undescribed warbler presumed to belong to the genus Cisticola has been documented in Gabon, and is added here as Teke Cisticola (undescribed form) Cisticola [undescribed form].

Taxon 23629: A putatively undescribed swallow presumed to belong to the genus Riparia has been documented in central Ethiopia (Gedeon and Töpfer 2021). This is added as Ethiopian Martin (undescribed form) Riparia [undescribed form].

Taxa 24232–24234: With the description of a new race of the Ruby-throated Bulbul Rubigula dispar matamerah of Sumatra(Berryman and Collar 2023), new groups are created within Rubigula dispar. These are the Ruby-throated Bulbul (Yellow-eyed) Rubigula dispar dispar of Java and Bali and Ruby-throated Bulbul (Red-eyed) Rubigula dispar matamerah of Sumatra.

Taxa 24251–24259: Eaton et al. (2021) consider the Barusan Bulbul Pycnonotus porphyreus as a full species based on genomic, morphological, and vocal differences from other taxa of Olive-winged Bulbul Pycnonotus plumosus. New groups are thus created here: Olive-winged Bulbul (Olive-winged) Pycnonotus plumosus [plumosus Group] for all races except porphyreus, and a monotypic group Olive-winged Bulbul (Barusan) Pycnonotus plumosus porphyreus, of coastal western Sumatra and islands off west-central Sumatra.

Taxa 24325–24334: Sundaic and Philippine taxa of Yellow-vented Bulbul Pycnonotus goiavier are separated by deep mtDNA divergences and some aspects of song, and treated as separate species by Eaton et al. (2016). These are now separate groups here, as Yellow-vented Bulbul (Sunda) Pycnonotus goiavier [analis Group] and Yellow-vented Bulbul (Philippine) Pycnonotus goiavier [goiavier Group].

Taxa 25801–25804: The Short-tailed Babbler Pellorneum malaccense is treated as comprised of three species in Eaton et al. (2021), based largely on vocal and genetic differences. These are here treated as separate groups: Short-tailed Babbler (Mourning) Pellorneum malaccense malaccenseof the Malaysian Peninsula and Sumatra; Short-tailed Babbler (Leaflitter) Pellorneum malaccense poliogenys of eastern Borneo; and Short-tailed Babbler (Glissando) Pellorneum malaccense sordidumof western Borneo.

Taxa 25824–25826: The White-chested Babbler Pellorneum rostratum is treated as comprised of two species in Eaton et al. (2021), based largely on vocal and genetic differences. These are treated as separate groups here, as White-chested Babbler (Malayan) Pellorneum rostratum rostratumof the Malaysian Peninsula and Sumatra, and White-chested Babbler (Bornean) Pellorneum rostratum macropterum of Borneo and the Banggai Islands.

Taxa 27639–27651: A new polytypic group of Tropical Mockingbird Mimus gilvus from southern Mexico to Belize, Tropical Mockingbird (Mayan) Mimus gilvus gracilis/leucophaeusis added. With the recognition of this new groups, the Mimus gilvus [gilvus Group] now ranges from Nicaragua and the Lesser Antilles south to eastern Brazil. Realignment of groups leaves the Isla San Andrés (w Caribbean Sea) Mimus gilvus magnirostris group unchanged.

Taxa 27889–27891: The Siberian Thrush Geokichla sibirica is now treated as two groups, the Siberian Thrush (Continental) Geokichla sibirica sibirica, which breeds over much of northern Asia, and the Siberian Thrush (Sakhalin) Geokichla sibirica davisoni, which breeds in Sakhalin and northern Japan.

Taxa 28293–28298: Two groups are now recognized for the Dark-sided Flycatcher Muscicapa sibirica, the northern-breeding Dark-sided Flycatcher (Siberian) Muscicapa sibirica sibirica and the subspecies that breed in the Himalayas and mountains of China, Dark-sided Flycatcher (Himalayan) Muscicapa sibirica [cacabata Group].

Taxa 28553–28558: The Large Niltava Niltava grandis is now treated as two groups, Large Niltava (Large) Niltava grandis [grandis Group], comprising three subspecies over most of the species’ range from the Himalayas through South-east Asia, and Large Niltava (Dalat) Niltava grandis decorata, of the Langbian Plateau of Vietnam, based on strong vocal differences (Eaton et al. 2016).

Taxa 29580–29584: Two new groups are formed within the newly split Fire-breasted Flowerpecker Dicaeum ignipectus s.s. These are Fire-breasted Flowerpecker (Fire-breasted) Dicaeum ignipectus/dolichorhynchum from most of the species’ range from Kashmir through the Malaysia Peninsula and Indochina, and Fire-breasted Flowerpecker (Taiwan) Dicaeum ignipectus formosum, from the mountains of Taiwan.            

Taxon 29687: An apparently new taxon of sunbird has been documented in the Rubeho Mountains of Tanzania (https://budgetbirders.com/2021/07/08/a-new-species-of-sunbird/). This is now included as Mafwemiro Sunbird (undescribed form) Anthreptes [undescribed form].

Taxa 29941–29948: The newly split Ornate Sunbird Cinnyris ornatus is comprised of two groups, one new and one that previously existed as a group within the Olive-backed Sunbird Cinnyris jugularis s.l. species. The new group is Ornate Sunbird (Ornate) Cinnyris ornatus [ornatus Group], from most of the species’ range, from the Andaman Islands and Myanmar through South-east Asia and Indonesia through the Lesser Sundas. The pre-existing group is the Ornate Sunbird (Cream-bellied) Cinnyris ornatus rhizophorae of southern China, Hainan, and northern Vietnam, in which the male differs strikingly in plumage from other taxa.

Taxa 31673–31679: The Long-tailed Rosefinch Carpodacus sibiricus is divided into two groups, which on the basis of Liu et al. (2020) are considered species by Gill et al. (2022, IOC v.12.1). These are the Long-tailed Rosefinch (Siberian) Carpodacus sibiricus [sibiricus Group] of north-central to northeastern Asia, with three subspecies, and the Long-tailed Rosefinch (Chinese) Carpodacus sibiricus lepidus/henrici group, with two subspecies.

Taxa 31768–31775: The Asian Rosy-Finch Leucosticte arctoa is now treated as two groups, the Central Asian group, Asian Rosy-Finch (Silver-winged) Leucosticte arctoa [arctoa Group], with three subspecies, and the mainly Siberian group Asian Rosy-Finch (Tawny-naped) Leucosticte arctoa brunneonucha/gigliolii, with two subspecies.

Taxa 32195–32201: The Meadow Bunting Emberiza cioides is divided into two groups, a continental central and east Asian group, Meadow Bunting (Rufous-eared) Emberiza cioides [cioides Group] and an insular group, Meadow Bunting (Black-eared) Emberiza cioides ciopsisof Sakhalin and the south Kuril Islands and Japan.

Taxa 33327–33331: A morphological and genetic study using mtDNA showed that the Common Grackle Quiscalus quiscula is comprised of two main clades (Capainolo et al. 2023) that are non-congruent with previously defined groups in Clements et al. (2023). Following this analysis, we recognize the new group Common Grackle (Florida) Quiscalus quiscula quisculaof the southeastern United States as a separate group from the Common Grackle (Purple) Quiscalus quiscula stonei of much of the eastern United States.

Range Changes

Taxon 1936: The range statement of the Black Wood-Pigeon Columba janthina janthina is modified to add islets off Taiwan.

Taxon 3025: The range statement of the Smooth-billed Ani Crotophaga ani has been modified to indicate its introduced status to the Galápagos Islands and to better summarize its present status in Florida.

Taxon 3243: The range statement of the Great Lizard-Cuckoo Coccyzus merlini bahamensis is modified to indicate uncertainty as to its continued survival on New Providence Island of the Bahamas.

Taxon 3357: The range statement of the Moluccan Cuckoo Cacomantis aeruginosus heinrichi is modified to add the island of Obi (Wu et al 2022).

Taxon 3687: The range statement of the undescribed Timor form “Timor Nightjar” of Caprimulgus (undescribed form) is modified to include Rote and Wetar.

Taxa 3724–3725, 3728–3729: The range statement of the Savanna Nightjar (Northern) Caprimulgus affinis [monticolus Group] is modified to clarify that it occurs in the northern Malayan Peninsula and throughout most of Southeast Asia. The range statement of the Savanna Nightjar (Sunda) Caprimulgus affinis [affinis Group] is modified to indicate its occurrence in the southern Malayan Peninsula, including Singapore (Puan et al. 2020).

Taxa 3869–3870: A range statement is added for Band-rumped Swift (spinicaudus) Chaetura spinicaudus spinicaudus, and the range of Chaetura spinicaudus aethalea was slightly modified for precision.

Taxa 3963–3965: The range statements of the Sulawesi Swiftlet Aerodramus sororum, Halmahera Swiftlet Aerodramus infuscatus, and Seram Swiftlet Aerodramus ceramensis are modified to include new information and to reflect uncertainty of taxa inhabiting Sangihe, Siau, Bacan, and Obi.

Taxon 5584: The spelling of the island Kosrae is corrected in the range statement of the extinct Kosrae Crake Zapornia monasa.

Taxa 5586–5588: The Ocellated Crake Rufirallus schomburgkii has been documented at many new locations, and hence the range statements are modified according, although subspecies attribution remains conjectural for some.

Taxon 6163: With the addition of the Dunlin subspecies Calidris alpina centralis, the ranges of the nominate is modified to exclude the eastern part of its breeding range, and a range statement is added for C. a. centralis.

Taxon 6628: A recent analysis (Mullarney and Campbell 2022) provides an improved understanding of the identification of non-breeding plumages of Saunders’s Tern Sternula saundersi and has led to the realization that the species’ non-breeding distribution must differ dramatically from the previously accepted range (e.g., Clancey 1982, Turner and Pearson 2015, Allport et al. 2022). Rather than wintering widely in the Red Sea and East African coasts, and to the Malay Peninsula, saundersi evidently winters mainly in the Seychelles to Maldives and Cocos (Keeling) Island (Mullarney and Campbell 2022), and thus the distributional statement is modified accordingly. In addition, the breeding range is modified to specify islands between India and Sri Lanka (e.g., Panagoda et al. 2020).

Taxon 7691: The range statement for the Oriental Honey-buzzard (Indomalayan) Pernis ptilorhynchus ruficollis/philippensis is modified to indicate its wider occurrence in southwestern China than previously indicated and that it occurs throughout Southeast Asia except for the Malayan Peninsula (Cheng 1987, Wells 1999, Ferguson-Lees and Christie 2001, MacKinnon 2022).

Taxon 8067: The breeding range of the Japanese Sparrowhawk Accipiter gularis sibiricus is modified to exclude Taiwan.

Taxon 8361: A range statement is added for the undescribed “Elgin Buzzard” Buteo of the southwestern Cape, South Africa.

Taxon 8832: Correction from “Nayari” to “Nayarit” in range statement of Ferruginous Pygmy-Owl Glaucidium brasilianum cactorum.

Taxon 9354: The range statement of the Amazonian Black-throated Trogon Trogon rufus sulphureus is modified to include northern Bolivia (Herzog et al. 2019).

Taxa 9476–9479: Ranges of Western Long-tailed Hornbill Horizocerus albocristatus and Eastern Long-tailed Hornbill Horizocerus cassini are revised to include Sierra Leone in the range of Horizocerus albocristatus albocristatus; to include Togo in the range of Horizocerus albocristatus macrourus; and to include Benin in the range of Horizocerus cassini.

Taxon 10062: The range statement of the Dollarbird Eurystomus orientalis orientalis is modified to better reflect its distribution within South Asia and to correct the spelling of Halmahera.

Taxon 10493: The range statement of the Blue-eared Barbet Psilopogon cyanotis cyanotis is modified to indicate northern Malay Peninsula to indicate its limited regional distribution.

Taxon 12932: The range statement of the Green Parakeet (Red-throated) Psittacara holochlorus rubritorquis is modified to reflect its occurrence away from highlands.

Taxon 12934: The range statement of the Pacific Parakeet Psittacara strenuus is modified to reflect its occurrence away from the arid zone.

Taxon 12943: The range statement of the more northerly subspecies of Cordilleran Parakeet Psittacara frontatus, Psittacara frontatus frontatus, is changed from western to southern Ecuador, as it occurs in the central (Andes) of southern Ecuador but not farther north.

Taxon 13029: The range statement of the Gray-lored Broadbill Serilophus rubropygius is changed to include western Yunnan, southwestern China (ML photos).

Taxa 13134, 13138–13139, 13142: For Nicobar Hooded Pitta Pitta abbotti, change Nicobar Islands to Great and Little Nicobar islands. For Western Hooded Pitta Pitta sordida mulleri, change Sulu Island to Sulu Islands; for Pitta sordida bangkana, change range to specify east of Sumatra; and for Pitta sordida palawanensis, modify range to clarify southwestern Philippines.

Taxon 13278: A range statement is added for the undescribed “Inirida Antshrike” Thamnophilus of Inírida, Guainía, Colombia.

Taxon 13296: The range statement of the Cocha Antshrike Thamnophilus praecox is revised to include the previously unknown Colombian and Peruvian portions of its range.

Taxon 14077: The range statement for Rusty-breasted Antpitta Grallaricula ferrugineipectus rara is revised to include a disjunct Cauca Valley, Colombian population of uncertain subspecies.

Taxon 14752: The range statement for the Pacific Hornero Furnarius cinnamomeus is modified to include Nariño, southwestern Colombia.  

Taxa 14987–14989: The range statement of Eastern Woodhaunter Automolus subulatus subulatus is modified to include southern Venezuela, while that of Automolus subulatus lemae is now southern Venezuela (Bolívar) (Hilty 2003).

Taxon 15052: The range statement of Streaked Tit-Spinetail (White-throated) Leptasthenura striata albigularisis modified to include new information (ML) showing that its range extends from at least Junín to Ayacucho, Peru.

Taxon 15126: The range statement of the Streak-backed Canastero Asthenes wyatti sclateri is modified to reflect the fact that the mountains of Córdoba, Argentina are not part of the Andes.

Taxon 15763: The range statement of the Cryptic Becard Pachyramphus salvini is modified to reflect its evidently seasonal occurrence on the east slope of the Andes.

Taxa 16154–16165: The range statements of the newly split Western Olivaceous Flatbill Rhynchocyclus aequinoctialis and Eastern Olivaceous Flatbill Rhynchocyclus olivaceus are modified to reflect occurrence of Rhynchocyclus aequinoctialis cryptus west into Amazonian Peru and Bolivia and to indicate the finding that Clade G, currently assigned to Rhynchocyclus olivaceus guianensis, also occurs in south Amazonian Brazil between the Purus and Tapajós rivers (Simões et al 2021).

Taxon 16313: The range statement of the Marañon Tyrannulet Nesotriccus maranonicus is changed to include the Ecuadorian portions of its range.

Taxa 16416–16419: The range statements for subspecies of Mountain Elaenia Elaenia frantzii are modified with new and more complete information (van Dort in litt. 2023).

Taxon 17854: The range statement of the Morotai Friarbird Philemon fuscicapillus is rectified to exclude islands other than Morotai, northern Moluccas.

Taxon 19223: The range statement of the Wetar Oriole Oriolus finschi is modified to include Atauro (East Timor).

Taxa 20064, 20067: Range statements of two subspecies of Ashy Drongo Dicrurus leucophaeus, Dicrurus leucophaeus nigrescens and Dicrurus leucophaeus bondi are modified to reflect current knowledge.

Taxa 22287–22291: The ranges of Asian Short-toed Lark Alaudala cheleensis are modified with the rejection of Alaudala cheleensis kukunorensis and recognition of Alaudala cheleensis seebohmi (Alström in litt. 2023).

Taxon 28043: The range statement of the northernmost subspecies of Clay-colored Thrush Turdus grayi tamaulipensis is modified to include southern Texas and to indicate uncertainty over the southern limits, as Mexican subspecies overlap extensively in range.

Taxon 28094: The range statement of the Black Thrush Turdus infuscatus is modified based on improved information.

Taxa 30975–30977: Clements (2007) recognized Robin Accentor subspecies Prunella rubeculoides fusca but not Prunella rubeculoides muraria,and included Xinjiang in the range of fusca, but this is considered geographically unlikely in Clements et al. (2023), in which Xinjiang is added to the range of the now-recognized muraria.

Taxon 31475: The range statement of the Chestnut-breasted Chlorophonia Chlorophonia pyrrhophrys is rephrased to adhere to geographical convention, and to reflect an apparently larger range within Peru than previously known.

Taxon 32833: The range statement of the White-eared Ground-Sparrow Melozone leucotis nigrior is modified to include the Honduran range.

Taxon 33526: The range statement of the Elfin-woods Warbler Setophaga angelae is revised to include its range in west-central Puerto Rico.

Taxon 34621: The range statement of the Red-legged Honeycreeper Cyanerpes cyaneus carneipes is revised to include more specific information for Mexico, and to add Cuba.

Linear Sequence Changes

Taxa 4736–4738: The sequence of subspecies of White-throated Mountain-gem Lampornis castaneoventris is revised to adhere to the north-to-south convention.

Taxa 5214–5225: With their reassignment to Sarothruridae as the genus Rallicula from Rallina, Rallicula rubra, R. leucospila, R. forbesi, and R. mayri are placed after genus Sarothrura.

Taxa 5382–5404: With the move of Cyanolimnas into Mustelirallus (Brown et al. 2022), the latter genus is moved to follow Pardirallus.

Taxa 5695–5703: The sequence of families Pluvianellidae and Chionididae is reversed, following the phylogeny of Černý and Natale (2022).

Taxa 5704–5730: Following the phylogeny of Černý and Natale (2022), the deeply diverged new genus Hesperoburhinus is placed first within Burhinidae, followed by Esacus, then Burhinus. Within Burhinus, species order as suggested by the phylogeny becomes capensis, vermiculatus, grallarius, and the oedicnemus/senegalensis clade, in which by convention the northernmost taxon oedicnemus precedes senegalensis, while the unsampled indicus is assumed to be sister to oedicnemus and is placed after it due to its more easterly distribution.        

Taxa 5781–5930: The linear sequence of Charadriidae is dramatically altered based largely on the phylogeny of Černý and Natale (2022) and its predecessors (Baker et al. 2007, Barth et al. 2013, dos Remedios et al. 2015). The deeply basal positions of Pluvialis and (to a lesser degree) Oreopholus are reaffirmed, but the relationships of other major clades shift markedly. It is now clear that the traditional genus Charadrius is highly paraphyletic with respect to other taxa, especially the lapwing Vanellus complex. WGAC and Clements et al. (2023) now recognize two major genera encompassing members of the former Charadrius, Charadrius s.s. and Anarhynchus, because many of the nodes within these clades that could be subdivided more finely are not well-supported and internal relationships remain unclear.

Vanellus cayanus is found to be a deeply diverged lineage of unclear relationships, and requires resurrection of the genus Hoploxypterus. Phegornis mitchelli is deeply diverged as expected, while Charadrius modestus is also deeply diverged and a distant sister to the morphologically dissimilar Phegornis, thus requiring resurrection of the genus Zonibyx. Charadrius morinellus is suggested to be the deeply diverged sister to all Charadrius s.s., and hence is returned to the genus Eudromias.

Charadrius s.s. now contains vociferus, hiaticula, semipalmatus, melodus, cucullatus, melanops, novaeseelandiae, forbesi, tricollaris, dubius, and placidus. This includes taxa long treated within the genera Thinornis and Elseyornis. The linear sequence of Vanellus (other than the removal of Hoploxypterus cayanus) is unchanged, but future changes both at the genus level and within the clade may well be warranted (Černý and Natale 2022).

The monotypic Australasian genera Erythrogonys and Peltohyas are evidently deeply diverged successive sisters to the remaining clade of Charadrius s.l., and while the first two continue to be treated as monotypic genera, the remaining taxa are placed within the oldest available genus, Anarhynchus Quoy and Gaimard, 1832, with A. frontalis as type species. Thus, Anarhynchus s.s. now contains asiaticus, veredus, mongolus, atrifrons, leschenaultii, bicinctus, frontalis, obscurus, wilsonia, collaris, montanus, alticola, falklandicus, thoracicus, pecuarius, sanctaehelenae, ruficapillus, nivosus, pallidus, peronii, marginatus, javanicus, alexandrinus, and dealbatus.

NACC and SACC (https://www.museum.lsu.edu/~Remsen/SACCprop979.htm) are currently considering proposals for linear sequence changes in the Charadriidae for Western Hemisphere species.

Taxa 5950–5974: The linear sequence of the Jacanidae is modified following the phylogeny of Černý and Natale (2022). In this phylogeny, monotypic Asian Hydrophasianus is the deeply diverged sister to the Neotropical Jacana clade, while the Microparra/Irediparra clade of Africa and Australasia, respectively and then Asian Metopidius,are deeply diverged sisters to Afrotropical Actophilornis.

Taxa 5975–6199: The linear sequence of the Scolopacidae is modified following the phylogeny of Černý and Natale (2022). In this newly modified sequence, major changes include that Prosobonia and Arenaria are deeply diverged but evidently sister taxa to Calidris, which, as the most derived clade of Scolopacidae, is now placed at the end of that family. The position in the phylogeny of Černý and Natale (2022) of Lymnocryptes minimus as deeply diverged sister to Scolopax rather than to Scolopacinae requires further corroboration before adoption, as these authors note. Scolopax minor is a deeply diverged sister to the Old World S. rusticola/mira clade and is thus placed first. Generic-level relationships within Gallinago and Coenocorypha, particularly involving imperialis and undulatus, remain to be clarified in a future study. Minor resequencing within core Scolopax brings the sequence closer to that in Černý and Natale (2022) and accords with geographical sequencing convention. Xenus was found to be a deeply diverged sister to Actitis, which was sister to the Phalaropus + Tringa clade (Černý and Natale 2022), and minor resequencing within core Tringa reconciles the sequence with that in Černý and Natale (2022).

Taxa 6201–6265: The linear sequence of Turnicidae is modified in accord with the sparse taxon sampling for this family in Černý and Natale (2022).

Taxa 6268–6215: The linear sequence of Glareolidae as in Clements et al. (2023) requires change in the 2024 update to present the genera in the order Glareola, Cursorius, and Rhinoptilus, according to the phylogeny of Černý and Natale (2022).

Taxa 6317–6335: The linear sequence of Stercorariidae is modified in accord with Černý and Natale (2022) and Mikkelsen and Weir (2023).

Taxa 6336–6404: The linear sequence of Alcidae is modified in accord with Černý and Natale (2022).

Taxa 6405–6739: The linear sequence of Laridae is modified in accord with Černý and Natale (2022).

Taxa 6812–6851: The linear sequence of genera of Diomedeidae is modified in agreement with the phylogeny in Estandía et al. (2021).

Taxa 7034–7035: The linear sequence of Cory’s Shearwater Calonectris diomedea diomedea is adjusted to place nominate diomedea (Scopoli’s Shearwater) adjacent to Cape Verde Shearwater

C. edwardsii. Mitochondrial DNA results suggest a sister relationship between these two taxa (Gómez-Diaz and Gonzáles-Solis 2007, Gómez-Diaz et al. 2009).

Taxa 7145–7162: The linear sequence of Fregatidae is modified in agreement with the phylogeny in Martins et al. (2022); see also Croxall (2023).

Taxa 7163–7193: The linear sequence of Sulidae is modified in agreement with the phylogeny in Patterson et al. (2011).

Taxa 7310–7544: The linear sequence of the Ardeidae is modified based on the phylogeny of Hruska et al. (2023). This shows Tigriornis to be a tiger-heron, though basal to Tigrisoma; Cochlearius and Agamia to be deeply diverged monotypic clades basal to all other ardeids; Zebrilus to be a deeply diverged sister of bitterns; the paraphyly of the Ixobrychus bitterns with respect to Botaurus; the non-monophyly of the night herons, which requires minor change to names; and the fact that Bubulcus is embedded within Ardea. The Ixobrychus and Bubulcus issues have not yet been resolved by Clements et al. (2023) by any generic changes; NACC is currently considering a proposal for linear sequence changes in the Ardeidae for North and Middle American species.

Taxon 8184: The linear sequence of Haliaeetus is modified to place Steller’s Sea-Eagle Haliaeetus pelagicusfirst, reflecting its basal phylogenetic position within the genus, when (as here) Icthyophaga is considered a separate genus (Mindell et al. 2018).

Taxa 9240–9392: The linear sequence of genera of Trogonidae is modified to reflect the phylogeny of Oliveros et al. (2019b).

Taxa 10337–10342: The Green Barbet Cryptolybia olivaceais not a member of Stactolaema with which it was formerly united, but may be more closely related to Gymnobucco and/or Buccanodon (Moyle et al. 2004). It is tentatively placed before Gymnobucco in Clements et al. (2023).

Taxa 11051–11056: The broad concept of Chloropicus as recognized by previous versions of Clements has now been reduced to three species, based on e.g., Fuchs et al. (2017a), Shakya et al. (2017). These three, Chloropicus pyrrhogaster, Chloropicus xantholophus, and Chloropicus namaquusare placed at the beginning of the sequence and are followed by Dendropicos.

Taxa 11913–11980: The genera of Cacatuidae are resequenced based on the phylogeny of Smith et al. (2022).

Taxa 12475–12476: With the split as a species of Black-billed Hanging-Parrot Loriculus bonapartei, that species is placed after Camiguin Hanging-Parrot Loriculus camiguinensis on geographical grounds.

Taxa 13063–13067: Based on its basal position in the phylogeny of Irestedt et al. (2013) to other Sulawesi region Erythropitta species, Erythropitta dohertyiis placed in the sequence before Erythropitta celebensis. Based on geographic convention, E. celebensis is moved to precede Sangihe Pitta Erythropitta caeruleitorques and Siau Pitta Erythropitta palliceps.

Taxa 13075–13081: The newly split Erythropitta habenichtiis placed in the sequence before E. macklotii, and Erythropitta macklotii digglesi, Erythropitta macklotii loriae, and Erythropitta macklotii finschii are sequenced thus on geographical grounds.

Taxa 14024–14029: The sequence of subspecies of Streak-chested Antpitta Hylopezus perspicillatus are modified based on north to south convention.

Taxa 14991–14996: Based on convention, the Automolus infuscatus cervicalis/badius group of northern South America is sequenced prior to the Amazonian Automolus infuscatus infuscatus/purusianus group.

Taxa 15092–15098: The sequence of subspecies of the Creamy-breasted Canastero Asthenes dorbignyi is revised to follow geographic convention.

Taxa 15121–15122: The sequence of subspecies phelpsi and mucuchiesi of the Streak-backed Canastero Asthenes wyatti is switched to follow geographical convention.

Taxon 15180: The Speckled Spinetail Thripophaga gutturata is resequenced to the beginning of Thripophaga from its previous position in Cranioleuca, based on the phylogeny of Harvey et al. (2020). ML images show that it does not have prominently spiny rectrix tips, so change to its English group name should be considered.

Taxon 15192: The Russet-mantled Softtail Cranioleuca berlepschi is resequenced before the Cranioleuca marcapatae/albiceps clade, as per the phylogeny in Harvey et al. (2020). ML images show that it has somewhat spiny rectrix tips, so change to its English group name should be considered.

Taxon 15670:  The White-tailed Tityra Tityra leucuraof southern Amazonia officially remains an unrecognized species. Its position in the sequence is unclear but it now follows Tityra inquisitor.

Taxa 17909–18160: Family Acanthizidae is resequenced based on synthetic work by E. Miller (unpubl. data) based on e.g., Selvatti et al. (2015), Marki et al. (2017), Norman et al. (2018), and Fjeldså et al. (2020).

Taxa 21316–21493: Family Petroicidae is resequenced by WGAC based on Loynes et al. (2009) and Christidis et al. (2011).

Taxa 21940–21941: The monotypic group Spike-heeled Lark (Beesley’s) Chersomanes albofasciata beesleyi is moved to precede the Spike-heeled Lark (Spike-heeled) Chersomanes albofasciata [albofasciata Group] based on geographic convention.

Taxa 21957–21965: The subspecies group Karoo Long-billed Lark (Benguela) Certhilauda subcoronata benguelensis/kaokoensis is moved to precede the Karoo Long-billed Lark (Karoo) Certhilauda subcoronata [subcoronata Group] based on geographic convention.

Taxa 22349–22358: The subspecies weigoldi of Oriental Skylark Alauda gulgula weigoldi is reordered following geographic convention.

Taxa 23492–23495: Striated Grassbird Megalurus palustrisis not a member of Cincloramphus and thus is repositioned to follow Fan-tailed Grassbird Catriscus brevirostris (Alström et al. 2018).

Taxa 23583–23885: The linear sequence of Family Hirundinidae is modified to follow the UCE phylogeny of Brown (2019).

Taxa 23886–24370: The linear sequence of Family Pycnonotidae is resequenced largely in accordance with Shakya and Sheldon (2017) and with a general preference for larger genera rather than many small genera (WGAC).

Taxon 24299: Styan’s Bulbul Pycnonotus taivanus is moved in the linear sequence to follow Light-vented Bulbul Pycnonotus sinensis. In the molecular phylogenetic analysis of McKay et al. (2013), which includes several subspecies of sinensis, taivanus is embedded with two of the sinensis taxa.

Taxon 24810: Phylogenetic data show that the former monotypic Javan endemic genus Pygmy Tit Psaltria exilis is embedded in the genus Aegithalos (Johansson et al. 2016), as enacted in Clements et al. (2022), and suggest its placement, as Aegithalos exilis, between White-cheeked Tit Aegithalos leucogenys and Black-throated Tit A. concinnus.

Taxa 26430–26546: The species of the family Sittidae have been resequenced to follow Päckert et al. (2020).

Taxa 28545–28699: Niltavinae genera from Leucoptilon to Cyornis have been resequenced to follow Zhao et al. (2023).

Taxa 29163–29164: With the finding that the White-winged Cliff-Chat, long known as Thamnolaea semirufa, is embedded in the genus Monticola (Zuccon and Ericson 2010a, b), it is moved in the linear sequence of Clements et al. (2023) to Monticola, as Monticola semirufus.

Taxa 29952–29954: The Banggai and Sula islands subspecies of the former Olive-backed Sunbird Cinnyris jugularis, Cinnyris jugularis robustirostris is moved from the Ornate Sunbird ornatus Group to the Sahul Sunbird Cinnyris frenatus, as Cinnyris frenatus robustirostris.

Taxa 33778–33779: Choco Warbler Myiothlypis chlorophrys is moved to precede Cuzco Warbler Myiothlypis chrysogaster based on geographic convention.

Taxa 34620–34632: The sequence of subspecies of Red-legged Honeycreeper Cyanerpes cyaneus is modified to follow geographic convention.

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Future Updates

The next annual revision that incorporates revisions to the taxonomy and nomenclature of the eBird/Clements Checklist is expected to be in conjunction with the release of the WGAC Checklist, in the fall of 2024.

Acknowledgments

Please continue to report potential errors, corrections, and suggestions for improvement of the eBird/Clements Checklist to cornellbirds@cornell.edu. Many errors easily slip through the cracks, so we greatly appreciate you letting us know of any that you find. If you can send a supporting reference or citation when reporting a potential change, that’s even more helpful. Thanks for whatever you can do!

Special thanks go to our many collaborators who carefully reviewed advance versions of this checklist, though of course any remaining errors are our responsibility. Max Kirsch deserves special thanks for his incredibly detailed review of our entire file, catching many hard-to-find errors in the process. We especially acknowledge Terry Chesser, for providing advance copies of work in progress, and to both Terry and to Van Remsen for their underappreciated roles in chairing the AOS regional classification committees (AOS-NACC and AOS-SACC, respectively). Special thanks also go to the hard-working members of NACC and SACC, who wrote and reviewed extra proposals in alignment with the WGAC process. David Donsker, Managing Editor of the IOC World Bird List https://www.worldbirdnames.org/new/, has played a huge role in alignment of the Clements and IOC lists, as well as on WGAC. And we are beyond grateful to members of IOU’s WGAC (Working Group Avian Checklist) for scientific input and discussions, specifically Juan Ignacio (Nacho) Areta, Paul Donald, Robert Dowsett, Frank Rheindt, and Richard Schodde who join Rasmussen, Schulenberg, Donsker, and Chesser in the Taxonomic group, Santiago Claramunt and Alan Peterson join Donald, Dowsett, Rasmussen, and Rheindt on the nomenclatural group (Working Group Avian Nomenclature or WGAN) and Donsker leads the WGAC bibliographic group. Most of our species-level updates this year have specifically aligned with WGAC decisions and we are excited about the collegiality and the process and look forward to the publication of the WGAC list in the coming year or two.

We also thank the following for their help in providing helpful comments on the eBird/Clements Checklist and related issues:

Mark Adams, Roger Ahlman, Margaret and Richard Alcorn, Desmond Allen, Gary Allport, Per Alström, Mike Andersen, Nick Anich, Juan Ignacio (Nacho) Areta, Christian Artuso, Gregory Askew, Nick Athanas, Dave Bakewell, Bruce Beehler, Louis Bevier, David Bishop, Elisa Bonaccorso, Alex Bond, Matt Brady, Kevin J Burns, Oscar Campbell, Heidi Ware Carlisle, Jamie Chavez, Les Christidis, Carla Cicero, Paul Clapham, Santiago Claramunt, Mario Cohn-Haft, Mich Coker, Jacob Cooper, Andrew Core, John Croxall, Jenna Curtis, Ian Davies, Glaucio Del-Rio, Paul Donald, Robert Dowsett, Andrew Dreelin, Jon Dunn, Pete Dunten,

James Eaton, Ted Floyd, Benjamin Freeman, John Garrett, Kimball Garrett, Jeff Gerbracht, Brian Gibbons, Mat Gilfedder, Frank Gill, Doug Gochfeld, Hector Gómez de Silva, Fabrico Gorleri, Phil Gregory, Alan Grenon, Cullen Hanks, Blanca E Hernández-Baños, Mark Holmgren, Peter Hosner, Praveen J, Gabriel Jamie, Alvaro Jaramillo, Rosa Jímenez, Oscar Johnson, Leo Joseph, Roselvy Juárez, Peter Kaestner, Laura Kammermeier, Brooke Keeney, Aiden Kiley, Max Kirsch, Alexander Kirschel, Guy Kirwan, Ethan Kistler, Yann Kolbeinsson, Peter Kovalik, Andrew Kratter, Dan Lane, Niels Larsen, Rafael Lima, Wich’yanan Limparungpatthanakij, Richard Littauer, Irby Lovette, Jakub Macháň, Nicholas Mason, Jay McGowan, Ryan Merrill, Eliot Miller, John Mittermeier, Steven Mlodinow, Nial Moores, Yann Muzika, Janette Norman, Raphaël Nussbaumer, Ryan O’Donnell, Scott Olmstead, Tommy Pedersen, Yoav Perlman, Shaun Peters, Alan Peterson, Vitor de Q. Piacentini, Hugh Powell, Thane Pratt, Michael Retter, Frank Rheindt, Don Roberson, Mark Robbins, Philip Round, Douglas Russell, George Sangster, Richard Schodde, Michael Schrimpf, Glenn Seeholzer, Luke Seitz, David Slager, Nicholas Sly, Andrew Spencer, Gary Stiles, John van Dort, Hein Van Grouw, Frank Willems, Johnny Wilson, Summer Wilson, Adam Winer, Kevin Winker, Kevin Zimmer, and Frank Zino.

We also extend grateful thanks to the wider community of eBird, Merlin, and BOW users; the many contributors to photo and sound archives whose combined work greatly facilitates taxonomy; the astute contributors to the Taxonomy and Nomenclature group on BirdForum, and our sincere apologies to any contributors we may have inadvertently overlooked.

Thanks everyone for your support, and we look forward to your continued feedback.

Pamela C. Rasmussen, Thomas S. Schulenberg, Marshall J. Iliff, Thomas A. Fredericks, Jeff Gerbracht, Denis Lepage, Andrew Spencer, Shawn M. Billerman, Brian L. Sullivan, and Christopher L. Wood, Cornell Lab of Ornithology.