Swallow tanager

The swallow tanager ("Tersina viridis") is a species of Neotropic bird in the tanager family Thraupidae. It is the only member of the genus Tersina. It is found widely throughout South America, from eastern Panama to far northern Argentina. The species is sexually dimorphic: the female is a yellow-green and the male a turquoise blue with a small deep black face and upper throat patch.
Taxonomy.
The swallow tanager was formally described in 1811 by the German zoologist Johann Karl Wilhelm Illiger under the binomial name "Hirundo viridis". The type type locality is eastern Brazil. The species is now the only member of the genus "Tersina" that was introduced in 1819 by the French ornithologist Louis Jean Pierre Vieillot. The genus name is from the French "Tersine", an unidentified bird described by Georges-Louis Leclerc, Comte de Buffon. The specific epithet "viridis" is the Latin for "green". A molecular phylogenetic study of the tanager family published in 2014 found that the swallow tanager is sister to the honeycreepers in the genus "Cyanerpes".
Three subspecies are recognised:
Description.
The swallow tanager is in length with a broad flat bill. This bird is strongly sexually dimorphic. The male is bright turquoise blue with a back face and throat. The turquoise flanks have black barring and the lower belly is white. The female is bright green with dusky-olive barring on the flanks. She lacks the black face mask. They are gregarious but do not associate with other species. They mainly eat fruit but they will also sally after insects from an exposed perch. The swallow tanagers are unique among tanagers in that they will sometimes dig a hole in a bank for a nest.