Acanthobunocephalus nicoi is the only species of catfish (order Siluriformes) in the genus Acanthobunocephalus of the family Aspredinidae. This species is known from only three localities and appears to be restricted to the upper Orinoco River system of Venezuela and possibly the upper Rio Negro system of Brazil. This species is found in flooded plants, primarily grasses and sedges, in black water (stained by tannin).