 They have a curved or humped back and a flat underside with a small terminal or sub-terminal mouth with a protruding lower jaw, the jaws are equipped with 3-5 rows of conical teeth.The dorsal fin has 12-16 spines and 10-14 rays, the anal fin has 3 spines and 6-9 rays.The outer ray of the ventral fins is the most elongated and the caudal fin has pointed lobes.