Description wikipedia

The bicolored antvireo (Dysithamnus occidentalis) is a Near Threatened insectivorous bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is found in Colombia, Ecuador, and Peru. == Taxonomy and systematics == The bicolored antvireo was described by the American ornithologist Frank Chapman in 1923. He considered it a subspecies of the white-shouldered antshrike (Thamnophilus aethiops) and coined the trinomial name Thamnophilus aethiops occidentalis. By the end of the twentieth century, it was widely accepted as a member of its present genus Dysithamnus . The bicolored antvireo has two subspecies, the nominate D. o. occidentalis (Chapman, 1923) and D. o. punctitectus (Chapman, 1924). Confusingly, punctitectus was originally described as a species in genus Dysithamnus while occidentalis was still in genus Thamnophilus. When occidentalis was moved to Dysithamnus and punctitectus was assigned as a subspecies, because occidentalis had been described first (even in a different genus) it became the nominate because of the principle of priority. == Description == The bicolored antvireo is about 13 to 13.5 cm (5.1 to 5.3 in) long. Adult males of the nominate subspecies D. o. occidentalis have a blackish gray head, upperparts, and tail with a mostly-hidden white patch between the scapulars. Their wings are black with white dots on the greater and median coverts and mostly white lesser coverts which are mostly hidden. Their underparts are a slightly lighter blackish gray than the upperparts. Adult females have a chestnut crown and upperparts with buffy white spots on the wing coverts. Their face, throat, and breast are dark grey with thin white streaks; their belly and crissum are olive-brown. Both sexes of subspecies D. o. punctitectus are paler than the nominate and their lesser wing coverts are completely white.