Large-billed antbird. Males are gray with white-spotted wings, and females are rusty-colored with gray sides to the head and buff-spotted wings. Occurs in humid forest with an open understory, where it forages at lower levels and on the ground, often in areas with large boulders covered with mosses and ferns; does not accompany mixed-species flocks. The song is a loud, descending series of notes that accelerate slightly at the end.