Schwarzscheitel-Ameisenvogel Percnostola rufifrons

Medium-sized, stocky bird of forest understory. Shows substantial geographic variation in plumage, but males are always black and dark gray, females rufous and gray-brown. Both sexes show thin wingbars: white in males, rufous-buff in females. Eastern populations (Guianas and NE Brazil) have striking red eyes; those of more western subspecies are gray. Found in tall rainforest and in lower-stature forests on sandy soils, usually in pairs or small groups that often follow army ants but are just as likely to be seen away from them, searching deliberately for insects in low vegetation. Not especially shy but often assesses observers warily from dense cover, pumping tail and giving low churring calls similar to other antbirds. Song is a series of clear, whistled notes on one pitch, with some geographic variation in pace; most common call is a sharp bark, similar to call of Black-faced Antthrush. In dim forest light, male may be confused with Spot-winged Antbird; Black-headed is best distinguished by wing bars (not spots), stockier profile, and vocalizations.