A small bird of reedbeds and flooded grasslands in the Trans-Fly of New Guinea. Black underparts and face, brown to blackish upperparts, yellow rump and tail, and a pale silver-blue bill. Usually seen in small flocks. Adult is distinctive in range, but juveniles similar to co-occuring White-spotted and Gray-crowned Munias, but juvenile Black Munias show more contrast between dark upperparts and paler underparts. Gives a short “twe-twee” call.