Head swollen and deep. Eye very small, 11 to 16 % of head length; snout very steeply rounded, but not swollen or projecting; mouth very large, strongly oblique; no barbel; no upper rostral pores; mental pores in one pair only, open behind symphysis; teeth well differentiated into large and small in both jaws; gill rakers long, slender, equal to or longer than gill filaments at angle, 16 to 18 on lower limb. Dorsal fin with VII to IX (most frequently VIII) spines. Second anal spine long, slender, 31 to 44 % of head length; caudal fin acutely pointed. Swim bladder hammer-shaped, with 11 pairs of arborescent appendages along its side, the first pair entering head beyond transverse septum and sending a palmate branch to the front of pectoral arch. Sagitta (large earstone) with tadpole-shaped impression, the head of which has its long axis lying obliquely to that of sagitta and the tail expanded and deepened as a hollow cone connected with the head by a narrow groove.