Golden-crowned warbler
The golden-crowned warbler is a small insectivorous bird in the New World warbler family Parulidae. It has a large geographic range that extends from northeastern Mexico south to northern Argentina. The white-bellied warbler was formerly treated as a separate species but is now considered to be conspecific with the golden-crowned warbler.
Taxonomy
The golden-crowned warbler was formally described in 1830 under the binomial name Sylvia culicivora by the German accountant Wilhelm Deppe in a price list of specimens that had been collected in Mexico by Wilhelm's brother Ferdinand Deppe. The specific epithet combines the Latin culex, culicis meaning "midge" and -vorus meaning "eating". The golden-crowned warbler is now one of 12 species placed in the genus Basileuterus that was introduced in 1848 by the German ornithologist Jean Cabanis. The genus name is from Ancient Greek βασιλευτερος/basileuteros meaning "more kingly".Fourteen subspecies are recognised:Basileuterus culicivorus flavescens Ridgway, 1902 – central west MexicoBasileuterus culicivorus brasierii – northeast, central east MexicoBasileuterus culicivorus culicivorus – central south Mexico to north Costa RicaBasileuterus culicivorus godmani Berlepsch, 1888 – central Costa Rica to west PanamaBasileuterus culicivorus occultus Zimmer, JT, 1949 – west ColombiaBasileuterus culicivorus austerus Zimmer, JT, 1949 – central ColombiaBasileuterus culicivorus indignus Todd, 1916 – north ColombiaBasileuterus culicivorus cabanisi Berlepsch, 1879 – northeast Colombia and northwest VenezuelaBasileuterus culicivorus olivascens Chapman, 1893 – north, northeast Venezuela and TrinidadBasileuterus culicivorus segrex Zimmer, JT & Phelps, WH, 1949 – south Venezuela, west Guyana and north BrazilBasileuterus culicivorus auricapilla – central, east BrazilBasileuterus culicivorus azarae Zimmer, JT, 1949 – southeast, south Brazil, Paraguay, Uruguay and north ArgentinaBasileuterus culicivorus viridescens Todd, 1913 – east BoliviaBasileuterus culicivorus hypoleucus Bonaparte, 1850 – southwest Brazil and northeast Paraguay
The subspecies B. c. hypoleucus, with white underparts, was formerly considered to be a separate species, the white-bellied warbler. It is now treated as a conspecific with the golden-crowned warbler based partly on evidence from a molecular phylogenetic study published in 2010 which found that B. c. hypoleucus did not form a monophyletic clade within the complex.
Description
The golden-crowned warbler is in overall length. It has grey-green upperparts and bright yellow underparts. The head is grey with a black-bordered yellow crown stripe, a yellow or white supercilium and a black eyestripe. Sexes are similar, but the immature golden-crowned warbler is duller, browner and lacks the head pattern other than the eyestripe.The subspecies fall into four groups. The Central American culicivorus group is essentially as the nominate described above, the southwestern cabanisi group has grey upperparts and a white supercilium, the aureocapillus group of the southeast, has a white supercilium and orange-rufous crown stripe, and the single subspecies in the hypoleucus group with white, not yellow, underparts that occurs in south central Brazil.