Carcharhinus acronotus

Author: (Poey, 1860)

Field Marks:
A small grey shark with a moderately long rounded snout, fairly large eyes, a black spot on the underside of the snout tip, oblique-cusped serrated teeth in both jaws, upper teeth without cusplets, usually 12/11 rows of anteroposterior teeth, no interdorsal ridge, small pectoral fins, a small first dorsal with a short rear tip and a moderately large second dorsal with a short rear tip, and dusky to blackish markings on the second dorsal and upper caudal tip.

Diagnostic Features:
A small, relatively slender species (up to about 1.4 m). Snout moderately long and rounded; internarial width 1.4 to 1.7 times in preoral length; eyes horizontally oval or circular and moderately large, their length 1.6 to 1.7% of total length in specim,ens nver 80 cm Innn: uooer labial furrows short and inconspicuous; hyomandibular line of pores just behind mouth corners not conspicuously enlarged; gill slits short, third 2.7 to 3.2% of total length and less than a third of first dorsal base; usually 12/11 rows of anteroposterior teeth in each jaw half but varying from 12 to 13/11 to 12; upper teeth with moderately narrow, strongly serrated, strongly oblique cusps, and cwown feet with slightly coarser serrations but no cusplets; lower teeth with slightly oblique serrated cusps and transverse roots. No interdorsal ridge. First dorsal fin small and semifalcate, with pointed or narrowly rounded apex and posterior margin curving ventrally from fin apex; origin of first dorsal fin over pectoral free rear tip; inner margin of first dorsal short, less than a third of dorsal base; second dorsal fin moderately large, its height 2.6 to 2.9% of total length, inner margin short and 1.1 to 1.3 times height; origin of second dorsal over or slightly behind anal origin; pectoral fins small, falcate, with narrowly rounded or pointed apices, length of anterior margins about 15% of total length in individilals above 80 cm long; 161 to 181 total vertebral centra, 80 to 88 precaudal centra. Black or dusky tips present on second dorsal, dorsal caudal lobe, and sometimes preventral edge of ventral caudal lobe; underside of snout with a conspicuous dusky to black blotch.

Geographical Distribution:
Western Atlantic: North Carolina to Florida, Bahamas, Gulf of Mexico, Virgin Islands, Puerto Rico, Antilles, Guyana, Venezuela, southern Brazil.

Habitat and Biology:
A common coastal tropical and warmtemperate shark of the continental and insular shelves, mainly over sandy, shell and coral bottoms. Off southwestern Florida pregnant females occur from January to April, and most individuals are caught from March through November, indicating a local migration.

Viviparous, with a yolk-sac placenta; number of young 3 to 6 per litter. Thought to mature in about two years; mates in spring.

The blacknose shark feeds on small fishes, including pinfish (Sparidae) and porcupine fish. This small, harmless shark is eaten by larger sharks. In captivity the blacknose shark performs a “ hunch” display, with back arched, caudal lowered and head raised, when confronted by divers or newly-introduced conspecifics. This is thought to be a possible threat display.

Size:
Maximum possibly 200 cm, males maturing between 97 and 106 cm, females maturing at about 103 cm and reaching at least 137 cm; size at birth between 38 and 50 cm.

Interest to Fisheries:
Caught mainly off southeastern Florida and northeastern Venezuela, but also caught elsewhere in its range. Caught mainly on surface longlines and utilized dried salted for human consumption.

Type material:
Holotype: Adult or adolescent male 980 mm, extant? Type Locality: Cuba.

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