Snout long 36-50% of head length; head length 7.1-10.1 in SL; ridge along top of snout and head low, no spines along side of snout; adult with no ridge along upper operculum; along side of body ends at level near anus or joins upper or lower tail ridge; upper ridge of body discontinuous with that of tail just behind dorsal fin; ridges along bottom of body and tail joined; body ridges not elevated; body and tail rings 14-16+ 34-39; usually no skin flaps; anal fin 2-4; dorsal fin 26-33, fin low, its origin on trunk; pectoral fin 10-14; tail fin large, 10; brood pouch under tail, its plates folded inwards.
Generally greenish, frequently with dark midlateral stripe and/or series of dark bars on side.
Reaches maximum size of 19 cm.
Usually among vegetation (or buried in sand at low tide) in bays and estuaries, occasionally among floating Sargassum.
Depth: 0-20 m.
Southern California to the Gulf of California to Peru.