OSME Region List ORL

OSME Region List of birds

A consultative document

Semi-collared Flycatcher

Semi-collared Flycatcher Ficedula semitorquata - an OSME speciality © Aurélien Audevard

The OSME Region List of Bird Taxa – Version 3.3-α1

The aim of the OSME Region List (ORL) is to provide a definitive list of bird taxa2 that have been recorded in the OSME Region. This Formal Edition is issued with a version number so that we* can implement amendments from the results of new research and from comments, corrections and suggestions we may receive. The ORL will be the basis of any country-by-country checklist for the OSME Region, a project that is being undertaken separately under the aegis of OSME Council in cooperation with the countries involved. A longer-term aim is to produce the ORL and country checklists in the languages of each country. However, before you examine the ORL for the first time, we suggest that you read its Ornithological basis, and the Explanation of the ORL. The Ornithological basis provides the rationale for the Order, Sequence and Nomenclature adopted in the ORL. For ease of reference, the ORL comprises five sections: Part A is the list of Non-passerines, Part B contains the Non-Passerine References, Part C is the list of Passerines, Part D contains the Passerine References and Part E comprises the Hypothetical list (species that are of unproven occurrence, those that are unlikely to occur and some perhaps that are both). We acknowledge here the help freely given and the interest expressed by so many people from throughout the Region and from the ornithological world – we believe that we have included their names in the Acknowledgements section below, but if you have been omitted, we apologise, and do let us know so that we can update it! A Simplified ORL (SORL – see http://osme.org/sites/default/files/SIMPLIFIED_ORL_2016_3.3.1.pdf) intended for use in routine correspondence and as a reference source of taxa names in non-taxonomic papers is derived from the published version of the ORL: the SORL usually is revised annually. The SORL is available in Excel format from the Listmaster.

*ORL correspondence coordinator; Listmaster, c ⁄ o The Lodge, Sandy, SG 19 2DL UK or via orl 

(ORL Team Founder Members and Co-authors: RICHARD PORTER AND †SIMON ASPINALL)

†Simon Aspinall died in October 2012, after a long illness. We’ll retain his name as an author of the ORL because his contributions form its core. A great naturalist, he was also a good and generous friend.

ORL 3.3: summary of changes

A major source of recent occurrence data was Arend Wassink’s The new Birds of Kazakhstan, from which many accounts, were updated. Those seabird species on the BirdLife Tracking Database that also occur in the OSME are identified in the ORL Non-Passerine and Hypothetical sections by a diagonally shaded pale blue fill in the relevant English name cells. We would be interested in feedback.

Kennedy and Spencer 2014 showed that the Great Cormorant taxon in most the OSME Region, sinensis (also in inland Europe) is as distant from Phalacrocorax carbo as is P. lucidus, White-breasted Cormorant, the African taxon that just reaches Yemen’s Red Sea coast. A Striped Crake Aenigmatolimnas marginalis from sub-Equatorial Africa turned up in Kuwait, first for the OSME Region, after having been taken for the similar Spotted Crake Porzana (now Zapornia) parva. Lesser Moorhen, another African rail, (3 records Oman) has now been allotted the genus Paragallinula Sangster et al 2015. The seriously declining and distinctively-plumaged alboaxillaris taxon of Eurasian Whimbrel Numenius phaeopus appears to breed in tiny numbers irregularly in Kazakhstan (Kohler et al 2013) and so has been accorded its own account in the ORL; its taxonomic status is uncertain. Huang & Tu 2016 establish clades in Tringa and Calidris via DNA barcoding, improving understanding of relationships.

In common with an increasing number of species with Nearctic and Palearctic populations, Lapland Owl Strix lapponica has been split by Robb and the Sound Approach 2015 from Great Grey Owl S. nebulosa, the vocal differences reinforcing the molecular conclusions of Nijman and Aliabadian 2013 (The Nearctic taxa may be split further, given that Hull et al 2014 have formally proposed yosemitensis as a new species). Another similar split from Robb and the Sound Approach 2015 and Nijman and Aliabadian 2013 concerns Boreal Owl Aegolius funereus: the sole Nearctic form becomes Aegolius richardsoni (seemingly there is some debate in the New World whether to call this taxon Richardson’s Owl or Boreal Owl), but presumably the single south Asian (beickianus) and the five Palearctic (funerus, pallens, caucasicus and the extralimital magnus, sibiricus) are included as sspp under A. funereus, which pleasingly reverts to the English name Tengmalm’s Owl. The Speckled Piculet has long been included in the genus Picumnus, the nominate being in the Region in Afghanistan and extralimital in Tibet and India, two other sspp occurring as far east as Borneo, but the other 26 species in the genus occur in South America. It will come as no surprise that Dufort 2015 shows that that Speckled Piculet belongs in its own genus, Vivia, and by case agreement the species name becomes innominata.

A molecular analysis by Zhan et al 2015, employing a battery of molecular techniques, concludes that Saker Falcon Falco cherrug is essentially monotypic: although plumage differences between cherrug and milvipes populations had long been cited as the rationale for dividing populations (sometimes populations being elevated to ssp status, eg Karyakin 2011) into these two groups, Zhan et al 2015 found examples of the supposed plumage differences within each group. However, the analysis of Fuchs et al 2015, employing a different suite of techniques, found Saker Falcon was not monophyletic! There is clearly much yet to be learned, but pro tem the ORL will refer to ‘cherrug-type’ populations under the informal name of ‘Northern Saker Falcon’ and to ‘milvipes-type’ populations under the informal name of ‘Southern Saker Falcon’.

An in depth revision of the Phylogeny of True Geese by Ottenburghs et al 2016 reveals ancestral Bar-headed Goose Anser indicus is basal to Branta and Anser genera. Amongst other discoveries, they found Swan Goose A. cygnoides to be sister to Greater (A. albifrons) and Lesser (A. erythropus) White-fronted Geese and to Tundra Bean Goose A. serrirostris.

Red’kin et al 2015 review the taxonomy of numerous Russian taxa, in passing largely adopting the same treatment of the large grey shrikes as in the ORL since 2010.  Stervander et al 2016 applied a suite of molecular techniques to Greater Short-toed Lark Calandrella brachydactyla and sister taxa: dukhunensis differs greatly from all others and pro tem we suggest informally the English name Sykes’ Short-toed Lark (from Sykes 1832); also eremica, formerly grouped with Blanford’s Lark C. blanfordi, is distant from all other Blanford’s Lark taxa and pro tem we suggest the informal English name of Arabian Short-toed Lark.

Olsson et al 2016 examined the morphology and molecular phylogeny of the Eurasian Reed/Mangrove Reed/African Reed Warbler (Acrocephalus scirpaceus/avicenniae/baeticatus) complex and found 8 lineages. They concluded that the reed warbler populations from Iberia through North Africa belonged not to African Reed Warbler A. baeticatus, as recently proposed, but to a new species, A. ambiguous, which may occur in the OSME Region in oases in westernmost Egypt; when previously placed in A. baeticatus it had been recorded in oases in easternmost Libya. No English name has been proposed, but pro tem we suggest Brehm’s Reed Warbler (from Brehm 1857).

Revisiting the Olsson et al 2013 seminal paper on the Lesser Whitethroat complex, it delineated the breeding distribution for the taxon margelanica as being the loess plateau of Northern China. Now Shirihai et al 2001 had elevated margelanica (Stolzmann 1897) to a full species, separate from Sylvia curruca, and indeed Olsson et al 2013 validate that approach, noting that margelanica is genetically quite different form curruca. However, the English name ‘Margelanic Whitethroat’ coined by Shirihai et al 2001 was based on specimens of migrant individuals passing through Margelan, Uzbekistan. We suggest informally the alternative English name ‘Cathay Whitethroat’, because the loess plateau lies within Cathay, the historical name for northern China. Wassink 2015 notes 3 records attributable to S. margelanica in south-east Kazakhstan. Furthermore, Votier et al 2016 employing a suite of isotope-ratio analyses demonstrate not only that the eastern taxa of the Lesser Whitethroat Sylvia curruca complex align with the conclusions of Olsson et al 2013, but also that taxa halimodendri and blythi show no evidence of intergrading; the corollary was that many morphology-based catalogued specimens attributed to other S. curruca taxa were unequivocally blythi.

White-tailed Rubythroat Calliope pectoralis has been split by Liu et al 2016 into extralimital Chinese Rubythroat C, tschebaiewi and polytypic Himalayan Rubythroat C. pectoralis, whose two ssp bailloni and the nominate both occur in the OSME Region. Hooper et al 2016 demonstrate that Rusty-tailed Flycatcher should be Ficedula ruficauda and not Muscicapa ruficauda. Lastly Li et al 2015 examine the molecular phylogeography and the population history of the white wagtail complex. It is not straightforward: haplotypes for alba, yarrelli, leucopsis & lugens were found in populations (in differing proportions) other than those identified as such, implying complicated population histories, perhaps even reallocation of taxa in some populations whose distribution limits are as yet unknown. This complexity is explained by white wagtails being extremely mobile across an extensive largely homogenous grassland habitat during the last glacial maximum, where populations met and separated often, resulting in extremely fast plumage divergence: the low genetic diversity reflects a mitochondrial history of less than 1 million years. We think it important to continue to list white wagtail taxa separately, so that none are lost from consideration and so that the weight of new data can be judged.

Thanks to Mike Jennings, I’ve now been able to go through all 30 issues of Phoenix and have incorporated numerous original contributions as cited references in the ORL. Version 6.3 of the IOC World Bird List has been taken into account in ORL3.3 proper, which supersedes the β-version. Lastly, observant readers will have noticed a considerable increase in ornithological papers from Chinese lead authors. We expect this to accelerate over the next few years as the investment China has made across the sciences takes effect in ornithology, especially in findings from biological molecular research.

References for ORL 3.3 Introductory Material

Dufort, M. 2015. An augmented supermatrix phylogeny of the avian family Picidae reveals uncertainty deep in the family tree. Mol. Phyl. Evol. 94(A). doi: 10.1016/j.ympev.2015.08.025

Fuchs, J, JA Johnson and DP Mindell. 2015. Rapid diversification of falcons (Aves: Falconidae) due to expansion of open habitats in the Late Miocene. Mol. Phyl Evol. 82: 166-182.

Hooper, DM, U Olsson and P Alström. 2016. The Rusty-tailed Flycatcher (Muscicapa ruficauda; Aves: Muscicapidae) is a member of the genus Ficedula. Mol. Phyl. Evol. Accepted.

Huang, Z and F Tu. 2016. DNA barcoding of Calidris and Tringa (Aves: Scolopacidae). Mitochondrial DNA 1-4. http://dx.doi.org/10.3109/24701394.2016.1155121

Hull, JM, A Englis Jr, JR Medley, EP Jepsen, JR Duncan, HB Ernest and JJ Keane. 2014. A new subspecies of Great Gray Owl (Strix nebulosa) in the Sierra Nevada of California, USA. Raptor Res. Found. 48(1): 68-77.

Karyakin, IV. 2011. Subspecies population structure of the Saker Falcon range. Raptors Conservation. 21: 116-172.

Kennedy, M and HG Spencer. 2014. Classification of Cormorants of the World. Mol. Phyl. Evol. 79: 249-257

Köhler, P, L Lachmann and R Urazliyev. 2013. Numenius species and subspecies in west Kazakhstan. WSG Bull. 120(1): 1=10

Li, X, F Dong, F Lei, P Alström, R Zhang, A Ödeen, J Fjeldså, PGP Ericson, F Zou and X Yang. 2015. Shaped by uneven Pleistocene climate: mitochondrial phylogeographic pattern and population history of White Wagtail Motacilla alba (Aves: Passeriformes). J. Avian Biol. doi: 10.1111/jav.00826

Liu, Y, G Chen, Q Huang, C Jia, G Carey, P Leader, Y Li, X Yang, F Zou, U Olsson and P Alström. 2016. Species delimitation of the White-tailed Rubythroat Calliope pectoralis complex (Aves, Turdidae) using an integrative taxonomic approach. J. Avian Biol. Accepted.

Nijman, V and M Aliabadian. 2013. DNA barcoding as a tool for elucidating species delineation in wide-ranging species as illustrated by owls (Tytonidae and Strigidae). Zool. Sci. 30: 1005-1009.

Olsson, U, P Leader, G Carey, AA Khan, L Svensson and P Alström. 2013. New insights into the intricate taxonomy and phylogeny of the Sylvia curruca complex. Mol. Phyl. & Evol.  doi: http://dx.doi.org/10.1016/j.ympev.2012.12.023

Olsson, U, H Rguibi-Idrissi, JL Copete, JLA Matos, P Provost, M Amezian, P Alström and, F Jiguet. 2016. Mitochondrial phylogeny of the Eurasian/African reed warbler complex (Acrocephalus, Aves). Disagreement between morphological and molecular evidence and cryptic divergence: a case for resurrecting Calamoherpe ambigua Brehm 1857. Mol. Phyl. Evol. Accepted.

Ottenburghs, J, H-J Megens, RHS Kraus, O Madsen, P van Hooft, SE van Wieren, RPMA Crooijmans, RC Ydenberg, MAM Groenen and HHT Prins. 2016. A Tree of Geese: A Phylogenomic Perspective on the Evolutionary History of True Geese. Mol. Phyl. Evol. 101: 303-313.

Red'kin, YA, VYu Arkhipov, SV Volkov, AA Mosalov and EA Koblik. 2015. [Type or species? Controversial taxonomic treatment of the birds of Northern Eurasia]. Вид или не вид? Спорные таксономические трактовки птиц Северной Евразии. [XIV Ornithological Conference of Northern Eurasia. II. Reports]. XIV орнитологическая конференция Северной Евразии. II. Доклады. [In Russian].

Robb, MS & the Sound Approach. 2015. Undiscovered Owls. The Sound Approach. Poole, UK.

Sangster, G, JC Garcia-Rodrigez and SA Trewick. 2015. A new genus for the Lesser Moorhen Gallinula angulata Sundevall, 1850 (Aves, Rallidae). Euro. J. Taxon. 153: 1-8.

Shirihai, H, G Gargallo and AJ Helbig. 2001. Sylvia Warblers. Identification, taxonomy and phylogeny of the genus Sylvia. Helm. A&C Black. London. UK.

Stervander, M, P Alström, U Olsson, U Ottosson, B Hansson and S Bensch. 2016. Multiple instances of paraphyletic species and cryptic taxa revealed by mitochondrial and nuclear RAD data for Calandrella larks (Aves: Alaudidae). Mol. Phyl. Evol. Accepted.

Votier, SC, S Aspinall, S Bearhop, D Bilton, J Newton, P Alström, P Leader, G Carey, RW Furness and U Olsson. 2016. Stable isotopes and mtDNA reveal niche segregation but no evidence of intergradation along a habitat gradient in the Lesser Whitethroat complex (Sylvia curruca; Passeriformes; Aves). J. Orn. doi 10.1007/s10336-016-1351-5

Wassink, A. 2015. The new Birds of Kazakhstan. De Cocksdorp. Texel, Nederland.

Zhan, X, A Dixon, N Batbayar, E Bragin, Z Ayas, L Deutschova, J Chavko, S Domashevsky, A Dorosencu, J Bagyura, S Gombobobaatar, ID Grlica, A Levin, Y Milobog, M Ming, M        Prommer, G Purev-Ochir, D Ragyov, V Tsurkanu, V Vetrov, N Zubkov and MW Bruford. 2015. Exonic versus intronic SNPs: contrasting roles in revealing the population genetic structure of a widespread bird species. Heredity 114: 1-9.

Version 3.2: summary of changes

As expected, there have been numerous taxonomic developments: a number of former Puffinus taxa have been transferred to a restored genus, Ardenna, making most groups monophyletic (Christides & Boles 2008); Purple Swamphen has been split (IOC5.3) pretty well as Garcia & Trewick 2015 had suggested and as ORL3.1 had forecast (from an early draft from Steve Trewick); Following Cohen 2011, we have revised most of the Sandgrouse, enlarging Syrrhaptes at the expense of Pterocles, but Cohen 2011 did not sample all taxa, and so further revision may occur; evidence has been advanced to elevate Cyprus Scops Owl to species rank (Robb & The Sound Approach 2015, Flint et al 2015); Desert Owl Strix hadorami (formerly Hume’s Owl S. butleri) and Omani Owl (now S. butleri but applied to differing geographical population(s)) are now identified, but distributions in part or in toto are uncertain – some recently-found widely-separated individuals in Iran are the latter species (Musavi et al 2016), but birds in the Eastern province of Saudi Arabia have yet to be identified (Kirwan et al 2015, Robb et al 2015); there have been minor changes of sequence of genera and within genera.

Miles et al 2015 show that song and morphology allow discrimination of Grasshopper Warbler Locustella naevia into eastern (straminea) and western (naevia) groups; molecular studies are needed to test this approach. Mason & Taylor 2015 found little or no genetic differentiation between Redpoll Acanthis flammea populations worldwide. Kamp et al 2015 revealed a decline of 94% in Yellow-breasted Bunting Emberiza aureola populations since 1980. The long-awaited Robins and Chats book (Clement and Rose 2015: 25 years in the making) appeared to much acclaim, providing several insights into OSME Region species, especially distributions, and some taxonomic interest, although the taxonomy in places was dated.

However, two non-taxonomic changes have added species to the ORL. Firstly, the OSME Region, with the agreement of the African Bird Club and the Oriental Bird Club, has extended its deep-ocean area south to 10°S, the result being as shown on the OSME website Home page. ABC and OBC have undertaken to consider where their respective deep-ocean boundaries should be designated, tasks which incorporate the Atlantic, Pacific and East Siberian Arctic Oceans. Initially, the OSME Region deep-ocean boundaries are shown as Great Circle lines or approximations to keep the initial limits simple and straightforward, but once ABC and OBC have formed their own policies, the OSME deep-ocean boundaries may, through joint discussion, be amended in future. We carried out a literature search for older papers referable to OSME Region sea areas, including the extension, and consequently confirmed occurrences that previously had been merely suspected. Furthermore, we visited regularly the BirdLife Seabird Tracking database (http://seabirdtracking.org/mapper/) and the BirdLife Marine IBA Inventory, (an amazingly detailed e-Atlas: http://maps.birdlife.org/marineIBAs/default.html) both, confirming additional species in the overall OSME sea area.

Secondly, many BirdLife Data Zone species distribution maps (http://www.birdlife.org/datazone/species) have been revised to show a much more nuanced distribution, especially because the maps incorporate splits BL have adopted via the Tobias et al 2010 (qv) criteria. For example, for high-altitude species, the shaded distribution does not include valleys. One consequence has been confirmation that some species do occur quite widely in eastern Afghanistan – see Orange Bullfinch Pyrrhula aurantiaca http://www.birdlife.org/datazone/species/factsheet/22720662.

The British Ornithologists’ Union, without any discussion with the members of its Taxonomic Sub-committee, has disbanded it, and will now take time to review the available global taxonomies with a view to adopting one system for all BOU activities. In our opinion, a modicum of joined-up thinking would have seen the BOU task the TSC to use its expertise to evaluate which global taxonomy best suited the BOU’s needs in the context of the validity of the assumption that any global taxonomic system would best suit all the BOUs needs. We consider the BOU’s decision to exclude the taxonomic expertise of the TSC in favour of an unknown level of expertise on which any decision on which taxonomic system the BOU will choose self-evidently to not be best practice. From the statement on the BOU website, it would appear the BOU went about the TSC disbandment for reasons of administrative convenience. As an aside, the final TSC report, Sangster et al 2015, provides critical reasons for the adoption of new (or resurrected) genera, enabling us to evaluate the original proposals for those recommended changes.

Lastly, recent research (Nebel et al 2015) gives the intriguing possibility that Golden Eagle Aquila chrysaetos may comprise at least two species and possibly more than three, but the data are insufficient for taxonomic conclusions.

References for Version 3.2 Introductory Material
Christidis, L and WE Boles. 2008. Systematics and Taxonomy of Australian Birds. CSIRO Publishing, Collingwood, VIC, Australia.
Cohen, C. 2011. The phylogenetics, taxonomy and biogeography of African arid zone terrestrial birds: the bustards (Otididae), sandgrouse (Pteroclidae), coursers Glareolidae) and Stone Partridge (Ptilopachus). Thesis. Univ. Cape Town. Clement, P and C Rose. 2015. Robins and Chats. Christopher Helm. London, UK.
Flint, PR, D Whaley, GM Kirwan, M Charalambides, M Schweizer and M Wink. 2015. Reprising the taxonomy of Cyprus Scops Owl Otus (scops) cyprius, a neglected island endemic. Zootaxa 4040(3): 301-316.
Garcia-Ramirez, JC and SA Trewick. 2015. Dispersal and speciation in purple swamphens (Rallidae: Porphyrio). Auk 132: 140-155.
Kamp, J, S Oppel, AA Ananin, YA Durnev, SN Gashev, N Hölzel, AL Mishchenko, J Pessa, SM Smirenski, EG Strelnikov, S Timonen, K Wolanska and S Chan. 2015. Global population collapse in a superabundant migratory bird and illegal trapping in China. Cons. Biol. DOI: 10.1111/cobi.12537
Kirwan, GM, M Schweizer and JL Copete. 2015.  Multiple lines of evidence confirm that Hume’s Owl Strix butleri (A. O. Hume, 1878) is two species, with description of an unnamed species (Aves: Non-Passeriformes: Strigidae). Zootaxa 3904 (1): 028–050.
Mason, NA and SA Taylor. 2015. Differentially expressed genes match bill morphology and plumage despite largely undifferentiated genomes in a Holarctic songbird. Mol. Ecol. doi: 10.1111/mec.13140
Miles, W, D Parnaby, B Rosser, J Moss and JM Collinson. 2015. 'Eastern Grasshopper Warbler' on Fair Isle: new to Britain. Brit. Birds 108: 231-236.
Musavi, SM, A Khani, A Khaleghizadeh and M Robb. 2016. The first confirmed records of Omani Owl Strix butleri (AO Hume, 1878) (Aves: Strigidae) from Iran. Zool ME XX
Nebel, C, A Gamauf, E Haring, G Segelbacher, A Villers and FE Zachos. 2015. Mitochondrial DNA analysis reveals Holarctic homogeneity and a distinct Mediterranean lineage in the Golden Eagle (Aquila chrysaetos). Biol. J. Linn. Soc. June 2015: 1-13.
Robb, MS & the Sound Approach. 2015. Undiscovered Owls. The Sound Approach. Poole, UK.
Robb, MS, G Sangster, M Aliabadian, AB van den Berg, M Constantine, M Irestedt, A Khani, SB Musavi, JMG Nunes, MS Willson and AJ Walsh, 2015. The rediscovery of Strix butleri (Hume, 1878) in Oman and Iran, with molecular resolution of the identity of Strix omanensis Robb, van den Berg and Constantine, 2013. bioRix preprint doi: http//dx.doi.org/10.1101/025122
Sangster, G, JM Collinson, P-A Crochet, GM Kirwan, AG Knox, DT Parkin and SC Votier. 2015. Taxonomic recommendations for Western Palearctic birds: 11th report. Ibis 158: 206-212.

Version 3.1: summary of changes

In Version 3.1, the ORL takes partly into account the information published in 2013 & 2014 in Complete Checklist of Birds of the World, volumes 1 &2, Passerines and Non-passerines, 4th Edition (H&M4:1 & H&M4:2). Much from these comprehensive, scholarly and heavily references volumes has been either omitted from the ORL pro tem or noted as possible changes, because it has yet to be interpreted in context by the IOC World Bird List on which the ORL essentially is based. For example, H&M4 contains many changes to the sequence of bird families, the sequence of genera within families and the sequence of species within genera. Furthermore, it adopts many new scientific names and some splits and lumps yet to be considered by IOC, but omits splits and lumps, some long-standing, already published by IOC. Moreover, it adopts more than a few new English names. The good news is that H&M4 provides a sound ‘audit trail’ of cited references for most of these differences from IOC decisions, allowing academic debate on the merits of the differences from published work: these differences are mostly of degree, and not fundamental disagreements. The ORL will adopt in principle the IOC evaluation of these differences as they are published.

 The publication of H&M4 has allowed the inclusion in the ORL of a much more comprehensive listing of and comment upon the subspecies that occur in the OSME Region. As a corollary, many ORL species have been positively classed as monotypic.

Several species new to the OSME Region have been added. The Strix owls of the Arabian Peninsula and Iran once considered as Hume’s Owl S. butleri appear to comprise two or, just possibly, three species: the most recent paper is Kirwan et al 2015; more are sure to follow. Green Bee-eater Merops orientalis is split in HBW into 3 species, all of which have been recorded in the OSME Region (del Hoyo et al 2014). A number of suspected or likely divergences in passerines have been quantified to varying extents, eg Barn Swallow Hirundo rustica (Scordato & Safran 2014), Cetti’s Warbler Cettia cetti (Alström et al 2011), Blue Rock Thrush Monticola solitarius (Zuccon & Ericsson 2010), Black-throated Accentor Prunella atrogularis (Drovetski et al 2013) & Water Pipit Anthus spinoletta (Garner et al 2015).

References for Version 3.1 Introductory material
Alström, P, S Höhna, M Gelang, PGP Ericson and U Olsson. 2011. Non-monophyly and intricate morphological evolution in the avian family Cettiidae revealed by multi-locus analysis of a taxonomically densely sampled dataset. BioMed Central http://www.biomedcentral.com/1471-2148/11/352
Drovetski, SV, G Semenov, SS Drovetskaya, IV Fadeev, YA Red’kin and G Voelker. 2013. Geographic mode of speciation in a mountain specialist Avian family endemic to the Palearctic. Ecol. & Evol. 1-11. doi: 10.1002/ece3.539
Garner, M, Y Perlman, Y Kiat and J Martin Collinson. 2015. Water Pipits: three species rather than one? Brit. Birds 108: 42-48.
del Hoyo, J, N Collar and GM Kirwan. 2014. Arabian Green Bee-eater (Merops cyanophrys). In: del Hoyo, J, A Elliott, J Sargatal, D Christie and E de Juana. Eds. Handbook of theBirds of the World Alive. Lynx Edicions, Barcelona.
Kirwan, GM, M Schweizer and JL Copete. 2015.  Multiple lines of evidence confirm that Hume’s Owl Strix butleri (A. O. Hume, 1878) is two species, with description of an unnamed species (Aves: Non-Passeriformes: Strigidae). Zootaxa 3904 (1): 028–050.
Scordato, ESC and RJ Safran. 2014. Geographic variation in sexual selection and implications for speciation in the Barn Swallow. Avian Research 5: 8 doi:10.1186/s40657-014-0008-4
Zuccon, D and PGP Ericson. 2010. The Monticola rock-thrushes: phylogeny, and biogeography revisited. Mol. Phyl. Evol. 55: 901-910


1 Our assessment of a number of papers for version 3.3 is preliminary, hence the adoption here of a beta (β) version; we’ll issue final version in July 2016.

2 We use the word ‘taxon’ (plural ‘taxa’) rather than ‘species’ or ‘subspecies’ here because there are a number of cases where any definition of a species or subspecies is inadequate to describe the status of populations where a majority of, but not all, individuals can be identified through visual identification, morphology or DNA studies. The subtleties revealed through much modern genetic research indicate that many more taxa than previously thought are in dynamic states of evolutionary stability that defy simple definitions of ‘species’ and ‘subspecies’ (the Yellow Wagtail Motacilla flava complex (qv) is a good example). Overlying this problem is that precise knowledge of taxa distribution limits and population numbers and densities is lacking over vast areas of the Region, which leads us to be cautious about even well-argued cases for ‘splitting’ and ‘lumping’. We therefore retain some taxa that we have not elevated to a higher rank and others that we have not ‘lumped’, but we note the cases for doing so.