Author: (Valenciennes, 1839)
Field Marks:
In its area the only requiem shark with long upper and lower labial furrows, small second dorsal fin with origin far behind anal origin, long anal ridges, and adpressed pectoral fin apex falling in front of first dorsal midbase. See key to species and diagnostic features for characters separating it from allopatric members of its genus.
Diagnostic Features:
Prenarial snout 4.4 to 5.1% of total length; upper labial furrows long, 1.4 to 2.1% of total length; total count of enlarged hyomandibular pores on both sides of head just behind mouth angle usually over 17 (6 to 14 on each side); teeth not serrate or irregularly serrate in adults; adult males with narrower, higher, more flex-cusped anterolateral teeth than adult females or immature males; total tooth rows usually 25/24. First dorsal origin over or slightly posterior to pectoral free rear tips: second dorsal origin usually above anal insertion but occasionally over the rear fourth of its base; pectoral anterior margin usually shorter than first dorsal length from origin to free rear tip; adpressed pectoral apex reaching to below first third of first dorsal base or falling behind it. Posterior monospondylous precaudal centra slightly enlarged; precaudal centra more numerous than caudals, precaudals 79 to 90, total centra 153 to 168. Size moderately small, males maturing at about 50 cm total length. Body dark grey or grey-brown above, light below, pectorals with light margins, dorsals dusky.
Geographical Distribution:
Western Atlantic: Panama to southern Brazil. 3
Habitat and Biology:
A common tropical littoral shark of the South American continental shelf, at depths of 3 to 70 m; prefers muddy and sandy bottoms, and not normally found in lagoons and estuaries.
Development viviparous, with a yolk-sac placenta; number of young 1 to 4 per litter. Mating season in summer.
Eats small bony fishes, including sardines and anchovies, as well as shrimp and squid.
Size:
Maximum about 77 cm, males maturing between 45 and 50 cm i and reaching 64 cm, adult females 54 to at least 77 cm; size at birth 33 to 34 cm.
Interest to Fisheries:
Fished in shallow water where it occurs, with bottom longlines, trammelnets, and probably other gear, and utilized dried salted for human consumption.
Type material:
Lectotype: Museum National d'Histoire Naturelle, ParisS MNHN 945, 303 mm, immature male, Brazil, designated by V. Springer (1964:619). Type Locality: Rio de Janeiro, Martinique, Guadeloupe.