Матугросская муравьянка Cercomacra melanaria

Medium-sized antbird with a long graduated tail. Males are black with a white-tipped tail and wing coverts. Females are olive-gray, paler below, with the same tail and wing patterns as the male. Inhabits the dense understory of gallery forest, swampy woodland, and deciduous dry forests, usually remaining deep in cover. Song is often a duet, with the male giving three buzzy frog-like notes and the female uttering high-pitched “chip-chip” notes.