<>Margariscus nachtriebi can be distinguished by the possession of the following characters: usually complete lateral line; 60-75 small lateral scales; short head; fairly deep caudal peduncle; flaplike barbel in groove above mouth (often missing on 1 or both side); almost cylindrical body; rounded snout; small, slightly subterminal mouth (seldom reaching front of eye); origin of dorsal fin behind origin of pelvic fin; 8 dorsal rays; 8 anal rays; and pharyngeal teeth 2,5-4,2. Body dark olive gray above, often with black herringbone lines, dark stripe along back; many small black and brown specks (absent in western populations) on silver side; white, yellow or red below; black stripe along side, black caudal spot on young; stripe vague on adult. Breeding male has bright orange-red lower side, pale yellow stripe along belly and many small tubercles on head (Ref. 86798).