Restricted to black or clear water drainages; common in Rio Negro-Casiquiare drainages, including the Pasimoni, Siapa and Emoni rivers, and black water tributaries of the upper Orinoco (Ref. 52916). Further north, this species is present in Ventuari drainages; to the east, common in Río Cuyuni drainage, and the northern distribution limit is Río Morichal Largo, a relatively isolated, clear-water drainage that flows into the Orinoco delta (Ref. 52916). Sympatric with Acestrorhynchus microlepis in southern Venezuela and the Guiana shield, but appears to be absent from the western and central llanos, presumably because of intolerance of prevalent white-water conditions (Ref. 52916).

Also Ref. 12225.