Distinguished by the following characteristics: small, stocky body with slightly depressed head; second dorsal and anal rays I, 6; pectoral scales absent in specimens from central Thailand, 10-12 predorsal scales present in southern (peninsular) specimens; pectoral girdle smoooth and with low fleshy flange; small eyes, mostly dorsal and close to snout tip; mouth terminal, large, may be greatly enlarged in males; deeply bilobed tongue; plain grey color, with blackish markings along bases of dorsal, anal, caudal and pectoral fins (Ref. 80545).