An impressively large and critically endangered bird found only in the remote Cerros del Sira mountain range in central Peru. Plumage is usually glossy black with a white vent and white tip to the tail, but a small number of females have mostly chestnut plumage. Both sexes have a bulbous blue casque on the forehead and a red bill. Inhabits lush cloud forest, where it usually remains on the ground. Song is an incredibly low-pitched hum; also gives soft grunts and clucks.