Author: (Springer, 1950)
Field Marks:
A large, deep-benthic grey shark with a long rounded or bluntly pointed snout, prominent anterior nasal flaps, high, triangular, serrated teeth without cusplets in upper jaw, erect narrow-cusped serrated teeth in lower jaw, usually 15/14-15 rows of anteroposterior teeth, a high interdorsal ridge, moderately high first dorsal fin, long, nearly straight pectoral fins, a moderately high second dorsal with a short rear tip and no conspicuous markings.
Diagnostic Features:
A large, fairly slender species (up to about 2.8 m). Snout moderately long and bluntly pointed to rounded; internarial width 1.3 to 1.4 times in preoral length; eyes circular and moderately large, their length 1.4 to 2.3% of total length; anterior nasal flaps rather high, triangular, and fairly broad; upper labial furrows short and inconspicuous; hyomandibular line of pores just behind mouth corners not conspicuously enlarged; gill slits moderately long, the third 3.1 to 3.9% of total length and about a third of first dorsal base; usually 15/14 to 15 rows of anteroposterior teeth in each jaw half but varying from 14 to 16/14 to 15; upper teeth with broad, strongly serrated, triangular, erect to slightly oblique, very high cusps that merge into the crown feet, the latter without coarse serrations or cusplets; lower teeth with erect, narrow serrated cusps and transverse roots. A prominent interdorsal ridge present. First dorsal fin moderately large and falcate, with bluntly pointed apex and posterior margin curving ventrally from fin apex; origin of first dorsal fin over pectoral insertion to about over midlength of pectoral inner margins; inner margin of first dorsal moderately long, half dorsal base or slightly less; second dorsal fin large and high, its height 2.8 to 3.4% of total length, its inner margin short and 1.1 to 1.4 times its height; origin of second dorsal slightly anterior to anal origin; pectoral fins large, hardly falcate, with narrowly rounded or pointed apices, length of anterior margins about 20 to 22% of total length; 194 to 206 total vertebral centra, 101 to 110 precaudal centra. Colour light grey above, sometimes bronzy, white below, with dusky fin tips (except for pelvics) but no conspicuous markings; white marking on flanks inconspicuous.
Geographical Distribution:
Western Atlantic: Florida, Bahamas, Cuba, Nicaragua, Costa Rica, Venezuela. Eastern North Atlantic: Senegal, Gambia, Sierra Leone, Ivory Coast and Ghana. Mediterranean Sea. Western Indian Ocean: South Africa, Madagascar, India, Red Sea. ? Western Pacific: China. Central Pacific: Hawaii. Eastern Pacific: Gulf of California, southern Mexico, Colombia, Ecuador, Revillagigedo Islands.
Habitat and Biology:
A common offshore, bottom-dwelling warm-temperate and tropical shark usually found in deeper water near the edge of the continental and insular shelves and the uppermost slopes, in depths of 90 m or more down to at least 250 to 430 m. The young may occur in shallower water, up to 25 m depth.
Development viviparous, number of young per litter 3 to 15. Mediterranean sharks give birth in August and September, Madagascar sharks September and October.
Eats a variety of bony fishes, including lizardfish, croakers, batfish, soles, other sharks including dogfish (Squalus), catsharks (Holohalaelurus), stingrays (Dasyatis), and cuttlefish. Although of large size, this species is probably not dangerous to people because of its deep-water habitat.
Size:
Maximum possibly about 300 cm, mature males 216 to at least 267 cm, mature females 226 to Z82 cm; size at birth probably between 70 and 90 cm.
Interest to Fisheries:
Apparently regularly taken in the Caribbean region on deep-set longlines (especially off Cuba, but also southern Florida), and there utilized for fishmeal, oil and shagreen; also taken in bottom trawls in the western Indian Ocean and probably by line or gillnet off India.
Type material:
Holotype: U.S. National Museum of Natural History, USNM 133828, 1320 mm immature female. Type Locality: Off Cosgrove Reef, Florida Keys, 174 m depth.