Anterior margin of pectoral fins straight or slightly convex; mouth subterminal; spiracles very small, subcircular and ventral to the plane of the pectoral fins; denticles mostly absent; tail whip-like and long, greater than disc width in embryos and juveniles, shorter than disc width in adults; caudal spine absent. Body colour greyish brown above; dorsal fin plain or
with a white tip; ventral surface mostly white.