Dorsal-fin spine short (table 1); dorsal fin reaching posterior edge of preadipose plate
when depressed in all species except Pseudancistrus sidereus where the dorsal fin does not
reach preadipose plate. Depressed pectoral-fin spine reaching beyond base of pelvic-fin
rays; depressed pelvic-fin spine typically reaching anterior insertion of anal fin (sometimes slightly beyond). Dorsal fin II7, caudal fin I14I, anal fin I4–5, pectoral fin I6, pelvic
fin I5.