Large forest guan found in far southeastern Peru, Bolivia, southwestern Brazil, and northern Paraguay, often along rivers. Plumage is mostly black with a white face, crown, nape, and wing patch. It has a bare patch of skin on the throat that may be light blue or white. On older birds this skin patch ends in a wormlike wattle that dangles below the neck. Formerly treated as a subspecies of Blue-throated Piping-Guan; it can be distinguished by the pure white (not buff-streaked) crown and nape, paler blue or white throat patch, and the wormlike wattle (on adults). In some areas, including the Pantanal, individuals with blue and red throat patches can be found; these are likely hybrids with Red-throated Piping-Guan. Mostly arboreal, but sometimes descends to the ground to feed or drink. Song, often given at dawn or dusk, is a rising series of clear whistles. Occasionally rattles its wings loudly in flight.