Author: (Richardson, 1836)
Diagnostic Features:
Prenarial snout 3.6 to 4.5% of total length; upper labial furrows long, 1.6 to 2.2% of total length; total count of enlarged hyomandibular pores on both sides of head just behind mouth angle usually over 16 (8 to 18 per side); teeth serrate in adults; teeth not differentiated in males and females; total tooth rows usually 25/24. First dorsal origin usually over or slightly in front of pectoral free rear tips; second dorsal origin ranges from above anal midbase to just in front of its insertion; pectoral anterior margin usually longer than first dorsal length from origin to free rear tip; adpressed pectoral apex reaching behind first third of first dorsal base. Posterior monospondylous precaudal centra enlarged; precaudal centra less numerous than caudals, precaudals 58 to 66, total centra 126 to 144. Size moderate, males maturing over 64 cm total length. Colour grey or grey-brown, white below, large specimens with small light spots, pectorals with white margins, dorsals with dusky tips.
Geographical Distribution:
Western North Atlantic: New Brunswick to Florida, Gulf of Mexico.
Habitat and Biology:
An abundant small coastal warm-temperate and tropical shark of the continental shelves; ranging from the intertidal to possibly 280 m deep, but usually in water less than 10 m deep. It often occurs close to the surf zone off sandy beaches, and also enclosed bays, sounds, harbours, and marine to brackish estuaries. It readily tolerates reduced salinities in estuaries and river mouths but does not penetrate far into fresh water. In the northern Gulf of Mexico it shows a regular inshore-offshore seasonal migration, retreating to deeper water with the onset of winter in October or November and returning inshore in spring, April and May.
Viviparous, with a yolk-sac placenta; number of young 1 to 7 per litter, most commonly 4 or 6 per litter, with larger. females carrying more young; the sex ratio of near term fetuses is 1:1. Off Texas, Florida and North Carolina young are born in late spring and summer (June to August). In the Gulf of Mexico mating occurs in late spring to summer, mid-May to mid-July, and are born in May or June after a 10 to 11 month gestation period. Gravid female sharks move into inshore waters to deposit their young, and in the northern Gulf of Mexico outnumber adult males by nearly 3:1.
Feeds on small bony fishes, including menhaden and other clupeids, snake eels, silversides, wrasses, small jacks, croakers, mojarras, toadfish, filefish, shrimp, crabs, segmented worms and molluscs (gastropod feet). It is harmless to people.
Size:
Maximum at least 110 cm, males maturing between 65 and 80 cm and reaching at least 103 cm, females maturing at 85 to 90 cm and reaching 110 cm; size at birth about 29 to 37 cm.
Interest to Fisheries:
A common inshore shark, fished in Mexican waters for food.
Type material:
Holotype: None? Type Locality: Newfoundland.