Diagnosed from all other freshwater fishes in Europe by its pelvic fin origin anterior to pectoral fin origin and by having one central barbel on lower jaw (Ref. 59043). Distinguished by the long second dorsal fin, at least 6 times as long as the first, and a single barbel on the chin (Ref. 27547). Gill rakers short (Ref. 27547). First dorsal short; second dorsal and anal fins joined to caudal; pectorals short and rounded; caudal rounded (Ref. 27547), with 40 rays (Ref. 2196). Color is yellow, light tan to brown with a pattern of dark brown or black on the body, head and fins (Ref. 1371). Pelvic fins pale, others dark and mottled (Ref. 27547).