Body covered with bony rings, 17 on trunk (gill slit to anus), 36 on caudal (anus to tail). No bony ridge on snout. Superior trunk ridge extending caudal region, ending dorsal fin end. Mid-lateral trunk ridge rising upwards from dorsal fin origin, continuing to superior caudal ridge at dorsal fin end. Inferior trunk ridge continuous to inferior caudal ridge. Dorsal fin 34 rays, its base on one trunk and 5 caudal rings. Anal fin minute, tip not reaching 2nd caudal ring. Brood-pouch on caudal, comprising 1st to 15th caudal rings. Pectoral fin length 1/3.5 of HL. Snout 1/2 of HL.
Distribution:
Coasts of Central and South America from Belize to Venezuela.
Remarks:
The present species is similar to S. floridae and S. pelagicus in most meristic and morphometric characters. Distinguishable from the former by large pectoral fin (S. floridae, about 1/7 of HL), the latter by short anal fin length (reaching to or beyond 2nd caudal ring in S. pelagicus) and larger size of brooding-male at least 225 mm SL (ca. 180 mm SL in S. pelagicus). (Shimizu)