Males possess only one Canestrini’s organ in the pectoral fin, and the plate of this organ is wide and short, usually not reaching the end of the third segment of the ray attached to it. Third Gambetta’s zone of pigmentation (stripe of small spots above large mediolateral spots) is usually poorly pronounced: not reaching the beginning of anal fin, often not reaching the end of pectoral fin. Oval shape scales, with relatively large central part lacking radial grooves and slightly displaced towards the anterior margin of the scale. Usually well developed cutaneous crests along dorsal and ventral margins of caudal peduncle. Short barbels, mandibular barbels usually not reaching the anterior margin of the eye in females and reaching slightly beyond anterior margin of eye in males. Body at the base of caudal fin with one very small narrow dark spot in the upper part (Ref. 93149).