The Arctic Warbler Phylloscopus borealis– three anciently separated cryptic species revealed

Abstract

The Arctic Warbler Phylloscopus borealis breeds across the northern Palaearctic and northwestern‐most Nearctic, from northern Scandinavia to Alaska, extending south to southern Japan, and winters in Southeast Asia, the Philippines and Indonesia. Several subspecies have been described based on subtle morphological characteristics, although the taxonomy varies considerably among different authors. A recent study (T. Saitoh et al. (2010) BMC Evol. Biol. 10: 35) identified three main mitochondrial DNA clades, corresponding to: (1) continental Eurasia and Alaska, (2) south Kamchatka, Sakhalin and northeast Hokkaido, and (3) most of Japan (Honshu, Shikoku, Kyushu). These three clades were estimated to have diverged during the late Pliocene to early Pleistocene (border at c. 2.6 million years ago). Differences in morphometrics have also been reported among members of the three clades (T. Saitoh et al. (2008) Ornithol. Sci.7: 135–142). Here we analyse songs and calls from throughout the range of the Arctic Warbler, and conclude that these differ markedly and consistently among the populations representing the three mitochondrial clades. Kurile populations, for which no sequence data are available, are shown to belong to the second clade. To determine the correct application of available scientific names, mitochondrial DNA was sequenced from three name‐bearing type specimens collected on migration or in the winter quarters. Based on the congruent variation in mitochondrial DNA, morphology and vocalizations, we propose that three species be recognized: Arctic Warbler Phylloscopus borealis (sensu stricto) (continental Eurasia and Alaska), Kamchatka Leaf Warbler Phylloscopus examinandus (Kamchatka (at least the southern part), Sakhalin, Hokkaido and Kurile Islands), and Japanese Leaf Warbler Phylloscopus xanthodryas (Japan except Hokkaido).

A review of the recent advances in the systematics of the avian superfamily Sylvioidea

“…No fewer than six species new to science have been described in that period: P. hainanus (Olsson et al, 1993), P. emeiensis (Alström and Olsson, 1995), S. omeiensis (Martens et al, 1999), S. soror (Alström and Olsson, 1999), P. occisinensis (Martens et al, 2008) and P. calciatilis . Moreover, taxonomic revisions have led to the recognition of several new species: P. canariensis and P. ibericus (previously treated as subspecies of P. collybita; P. ibericus formerly incorrectly called P. brehmii) (Helbig et al, 1996;Salomon et al, 1997;Helbig et al, 2001;Bensch et al, 2002;Salomon et al, 2003); P. orientalis (previously subspecies of P. bonelli; Helbig et al, 1995); P. borealoides (previously synonym of P. tenellipes ;Martens, 1988); P. chloronotus (previously subspecies of P. proregulus; Martens et al, 2004); P. forresti (previously synonym of P. proregulus chloronotus; Martens et al, 2004); P. kansuensis (previously synonym of P. p. proregulus;Alström et al, 1997;Martens et al, 2004); P. yunnanensis (previously synonym of P. proregulus chloronotus; nensis in latter study]; Martens et al, 2004); P. claudiae, P. goodsoni and P. ogilviegranti (two former previously subspecies of P. reguloides, third previously subspecies of P. davisoni; Olsson et al, 2005;Päckert et al, 2009); P. examinandus and P. xanthodryas (previously subspecies of P. borealis; Saitoh et al, 2006Saitoh et al, , 2008Saitoh et al, , 2010Reeves et al, 2008;Martens, 2010;Alström et al, 2011d); S. Family Phylloscopidae based on concatenated nuclear MB and mitochondrial cytochrome b and 12S sequence data, based on Olsson et al (2004Olsson et al ( , 2005, Alström et al (2006…”

The diversity and prevalence of hard ticks attacking human hosts in Eastern Siberia (Russian Federation) with first description of invasion of non-endemic tick species

“…Thus, hypothetically, any stage of A. americanum could survive trans-pacific migration. Finally, there are several bird species that perform annual migrations between Asia and North America, including the bar-tailed godwit (Limosa lapponica), the sandhill crane (Grus canadensis), the yellow wagtail (Motacilla flava), the arctic warbler (Phylloscopus borealis) and, most interestingly, a grey-cheeked thrush (Catharus minimus) that has been found to be responsible for the spread of A. americanum in Canada (Scott et al 2001;Gill et al 2009;Krechmer et al 1978;Ehrlich et al 1988;Alström et al 2011). The high possibility of regular tick migration between North America and Asia and associated pathogen transfer is also supported by recent findings of North American Powassan virus in ecosystems of Russian Far East (Leonova et al 2009;Deardorff et al 2013).…”

Taxonomic recommendations for British birds: eighth report

“…The taxon kennicotti is best treated as a synonym of borealis (Alström et al . ). Consequently, three monotypic species are recognized.…”

“…, Martens , Alström et al . ), and are best treated as separate species. Several names could potentially be used within this group.…”

“…() and the identity of these types is unclear, but the identities of the type specimens of flavescens Gray 1860, examinandus Stresemann 1913, and xanthodryas Swinhoe 1863 have been resolved, which has enabled names to be applied to the three species (Alström et al . ). The taxon kennicotti is best treated as a synonym of borealis (Alström et al .…”