Solitary Black Cacique

The male solitary cacique has a length of about 27 cm (10.6 in) and the female 23 cm (9.1 in). It differs from all other entirely black birds with dark irises within its range, by having a large white, chisel-shaped, sharply-pointed beak. It could be confused with the Ecuadorian cacique (Cacicus sclateri), but that is smaller and has a restricted range, or the yellow-billed cacique (Amblycercus holosericeus), but that is not found east of the Andes. It has a range of different vocalizations which are mostly delivered at a measured pace but are sometimes interrupted by gurgles and growls.

The solitary cacique has a very wide distribution in Amazonia. Its range extends southwards as far as northern Argentina and Uruguay at altitudes of up to about 800 m (2,625 ft). It inhabits forests, gallery forests and flooded areas. It is generally found in the mid-storey of the canopy, or the shrubby understorey, often clambering about among dense vines.

The solitary cacique is often found singly or in pairs but does not join flocks of birds. It forages in tangled undergrowth and is acrobatic, sometimes hanging upside-down. At times it visits flowering trees higher in the canopy. Its diet consists of invertebrates and small vertebrates such as tree frogs, and it also consumes fruit and nectar. Breeding takes place between October and January according to location and in Argentina it is thought that two broods are reared. Many birds in this genus build their nests in colonies, but this bird nests alone.