Gerygone

Large-billed gerygone Gerygone magnirostris, photographed by Lip Kee Yap.

Belongs within: Acanthizidae.

Gerygone is a genus of small insectivorous birds found in Australasia and south-east Asia. Most species feed by gleaning prey in the middle to upper canopies. The brown warbler G. mouki of south-eastern Australia and grey warbler G. igata of New Zealand may feed among lower vegetation than other species, with the grey warbler also feeding at ground level.

Riroriro
Published 6 May 2013
The grey warbler or riroriro Gerygone igata, photographed by Peter Bray.

The eighteen recognised species of the genus Gerygone are an assemblage of small, drab-coloured birds found mostly in the Australo-Papuan region, with G. sulphurea found in the Malay Peninsula, Indonesia and the Philippines, and G. flavolateralis found in New Caledonia and Vanuatu. These are another group of birds that have tended to draw the short straw in the vernacular name stakes: G. igata, one of the most abundant of New Zealand’s native birds, is usually identified by the uninspiring ‘grey warbler’. Personally, I prefer the more onomatopoeiac Maori name for these lively little birds: ‘riroriro’ (it has been suggested in some circles that it could possibly be referred to as the ‘grey gerygone’; this proposition shall be treated with the scorn that it deserves). The riroriro and its congeners feed on small insects that they mostly glean from leaves or small branches, generally in the middle to upper canopies (Ford 1985). A certain amount of their prey is caught in the air, while the riroriro and the brown warbler G. mouki of eastern Australia also forage in lower vegetation than other species. The riroriro is also the only Gerygone species known to forage on the ground (Keast & Recher 1997).

Gerygone species build hanging purse-shaped nests; this is a brown warbler Gerygone mouki photographed by Peter.

Somewhat unusually for a decently-speciose passerine genus, the circumscription of Gerygone has been fairly stable in recent years, and the genus has mostly been supported as monophyletic. The only exception of recent times has been the New Guinean G. cinerea, recently reclassified by Nyári & Joseph (2012) as a species of Acanthiza. In the early 1900s, some authors divided Gerygone species between smaller genera (for instance, the Australian ornithologist Gregory Mathews, who never met a genus he couldn’t break down). One species so separated was the Chatham Island warbler G. albofrontata, which is something of an island giant compared to other Gerygone species, weighing about 12 g while other species are about 6 to 7 g (Keast & Recher 1997). Unfortunately, the Chatham Island warbler was not included in the phylogenetic analysis of Gerygone by Nyári & Joseph (2012), but it was not identified as significantly separate from other Gerygone species in the morphological analysis by Ford (1985).

The Chatham Island warbler Gerygone albofrontata, from here.
Systematics of Gerygone

Characters (from Schodde & Mason 1999): Foreheads and faces usually plain; lores usually dusky with whitish supra-loral bars and orbital rings; songs sibilant, chromatic; nests pendulent, tailed, not communal.

<==Gerygone Gould in Grey 1841 (see below for synonymy)CC10
    |--+--G. chrysogasterBKB15
    |  `--G. moukiJT12
    |       |--G. m. moukiM03
    |       |--G. m. amaliaM03
    |       `--G. m. richmondiM03
    `--+--G. magnirostris Gould 1843BKB15, CC10 [=*Ethelornis magnirostrisCC10]
       |    |--G. m. magnirostrisM03
       |    |--G. m. brunneipectusM03
       |    `--G. m. cairnsensisM03
       `--+--+--G. igata (Quoy & Gaimard in Dumont d’Urville 1830)BKB15, CC10 (see below for synonymy)
          |  `--+--G. fusca (Gould 1838)BKB15, WS48 [=Psilopus fuscaCC10, *Wilsonavis fuscaCC10]
          |     |    |--G. f. fuscaWS48
          |     |    |--G. f. culicivora (Gould 1840)WS48 (see below for synonymy)
          |     |    `--G. f. exsulM03
          |     `--G. levigaster Gould 1842BKB15, WS48 (see below for synonymy)
          |          |--G. l. levigasterM03
          |          `--G. l. cantatorM03
          `--+--G. olivacea (Gould 1838)BKB15, WS48 [=Psilopus olivaceusWS48]
             |    |--G. o. olivaceaWS48
             |    |--G. o. cinerascensM03
             |    `--G. o. rogersi Mathews 1911 [=G. albigularis rogersi]WS48
             `--+--G. chloronota Gould 1842BKB15, WS48 [incl. G. chloronotus darwini Mathews 1912WS48]
                `--G. palpebrosaJT12
                     |--G. p. palpebrosaM03
                     `--G. p. flavidaM03
Gerygone incertae sedis:
  *G. albogularis [=*Psilopus albogularis, *Ostiarius albogularis]CC10
  G. albofrontata Gray 1845 (see below for synonymy)CC10
  G. cinereaJT12
  G. dorsalisJT12
  G. flavolateralisJT12
    |--G. f. flavolateralisS13
    `--'Pseudogerygone’ f. lifuensis Sarasin 1913S13
  G. hypoxanthaJT12
  G. inornataJT12
  G. insularisCC10 [=G. igata insularisCC10; incl. G. igata thorpeiD81]
  G. modesta Pelzeln 1860 (see below for synonymy)CC10
  G. personata Gould 1866G66 [=G. palpebrosa personataM03, *Pseudogerygone personataCC10]
  ‘Pseudogerygone’ rouxi Sarasin 1913S13
  G. ruficollisJT12
  G. sulphureaJT12
  G. tenebrosa (Hall 1901)JT12, WS48 (see below for synonymy)

Gerygone Gould in Grey 1841 [=Ostiarius Gistel 1848, Psilopus Gould 1838 non Poli 1795; incl. Ethelornis Mathews 1912, Hapolorhynchus Reichenow 1908, Maorigerygone Mathews & Iredale 1913, Pseudogerygone Sharpe 1879, Royigerygone Mathews 1912, Wilsonavis Mathews 1912; Gerygoninae]CC10

Gerygone albofrontata Gray 1845 [=Acanthiza albofrontata, *Hapolorhynchus albofrontatus, Pseudogerygone albofrontata]CC10

Gerygone fusca culicivora (Gould 1840)WS48 [=Psilopus culicivorusWS48; incl. G. culicivora dendyi Mathews 1912WS48, G. levigaster mungi Mathews 1912WS48, G. fusca mungiM03, G. culicivora wayensis Mathews 1912WS48]

Gerygone igata (Quoy & Gaimard in Dumont d’Urville 1830)BKB15, CC10 [=Curruca igataCC10, Acanthiza igataCC10, *Maorigerygone igataCC10, Pseudogerygone igataCC10, Psilopus igataCC10; incl. Gerygone assimilis Buller 1865CC10, G. aucklandica Pelzeln 1865CC10, Psilopus flaviventris Gray 1844CC10, Acanthiza flaviventrisCC10, Gerygone flaviventrisCC10, Maorigerygone igata flaviventrisCC10, Pseudogerygone flaviventrisCC10, Pse. macleani Ogilvie-Grant 1907CC10, Maorigerygone igata macleaniCC10, Gerygone sylvestris Potts 1873CC10, M. igata sylvestrisCC10, Pseudogerygone sylvestrisCC10]

Gerygone levigaster Gould 1842BKB15, WS48 [incl. G. levigaster broomei Mathews 1912WS48, Ethelornis levigaster perconfusus Mathews 1920WS48]

Gerygone modesta Pelzeln 1860 [=G. igata modesta, Pseudogerygone modesta, Royigerygone modesta, G. mathewsae Mathews 1912, *R. mathewsae]CC10

Gerygone tenebrosa (Hall 1901)JT12, WS48 [=Pseudogerygone tenebrosaWS48, G. magnirostris tenebrosaWS48; incl. G. tenebrosa christopheri Mathews 1912WS48, G. magnirostris whitlocki Mathews 1915WS48, G. tenebrosa whitlockiM03]

*Type species of generic name indicated

References

[CC10] Checklist Committee (OSNZ). 2010. Checklist of the Birds of New Zealand, Norfolk and Macquarie Islands, and the Ross Dependency, Antarctica 4th ed. Ornithological Society of New Zealand and Te Papa Press: Wellington.

[D81] Day, D. 1981. The Doomsday Book of Animals: A unique natural history of three hundred vanished species. Ebury Press: London.

Ford, J. 1985. Phylogeny of the acanthizid warbler genus Gerygone based on numerical analyses of morphological characters. Emu 86: 12–22.

[G66] Gould, J. 1866. Additions to the list of the avifauna of Australia, with descriptions of three new species. Proceedings of the Zoological Society of London 1866: 217–218.

[JT12] Jetz, W., G. H. Thomas, J. B. Joy, K. Hartmann & A. Ø. Mooers. 2012. The global diversity of birds in space and time. Nature 491: 444–448.

Keast, A., & H. F. Recher. 1997. The adaptive zone of the genus Gerygone (Acanthizidae) as shown by morphology and feeding habits. Emu 97: 1–17.

[M03] Morcombe, M. 2003. Field Guide to Australian Birds 2nd ed. Steve Parish Publishing.

Nyári, Á. S., & L. Joseph. 2012. Evolution in Australasian mangrove forests: multilocus phylogenetic analysis of the Gerygone warblers (Aves: Acanthizidae). PLoS One 7(2): e31840.

[S13] Sarasin, F. 1913. Die Vögel Neu-Caledoniens und der Loyalty-Inseln. In: Sarasin, F., & J. Roux (eds) Nova Caledonia: Forschungen in Neu-Caledonian und auf den Loyalty-Inseln. A. Zoologie vol. 1 pt 1 pp. 1–78, pls 1–3. C. W. Kreidels Verlag: Wiesbaden.

[WS48] Whittell, H. M., & D. L. Serventy. 1948. A systematic list of the birds of Western Australia. Public Library, Museum and Art Gallery of Western Australia, Special Publication 1: 1–126.

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