Body pentagonal shape and strongly compressed; head very deep with nape profile rounded and very steep, straight forehead-snout profile; lower gill rakers (excluding rudiments) 14-17; dorsal rays VIII+I, 17-20, spines of dorsal fin short, with at least last one isolated; anal rays II+I, 17-20; dorsal and anal fin spines become embedded with age; dorsal and anal fin lobes prolonged in adults; in juveniles front spines of dorsal and anal fins elongate and filamentous; pelvic fins elongate in juvenile, becoming very short in adults, anal spines filamentous; no isolated finlets after 2nd dorsal and anal fins; pectoral long, curved; straight part of lateral line with poorly developed, small scutes (hard spiny scales); scales very small, imbedded in skin, body appears scaleless.
Size: attains 31 cm.
Habitat: demersal on sandy bottoms; juveniles common in estuaries.
Depth: 1-50 m.
Southern Baja and the mouth of the Gulf of California to Ecuador.