Author: (Bonnaterre, 1788)
Field Marks:
A heavy-bodied, broad-headed sixgill shark, mouth ventral with 6 rows of lower bladelike, comb-shaped teeth on each side, one dorsal fin.
Diagnostic Features:
Body rather stout; size very large, to at least 4.8 m. Head broad and rounded to bluntly pointed; eyes small; lower jaw usually with 6 rows-of large, comblike teeth on each side, these with relatively short cusps. Caudal peduncle short and stout, distance from dorsal fin insertion to upper caudal origin about equal or slightly greater than length of dorsal fin base.
Geographical Distribution:
Wideranging in temperate and tropical seas. Western Atlantic: North Carolina to Florida, USA, northern Gulf of Mexico, Cuba, Nicaragua, Costa Rica, Venezuela, also southern Brazil to northern Argentina. Eastern Atlantic: from Iceland, Norway to Senegal, possibly Ivory Coast and Nigeria, Angola and Namibia, also Mediterranean Sea. Indian Ocean: Off South Africa, southern Mozambique, Madagascar, Aldabra Island group, Comores Islands. Western Pacific: Japan (eastern coast), Taiwan (Province of China), Malaysia, Sumatra, Australia (New South Wales and Victoria), New Zealand. Central Pacific: Hawaiian Islands, Palau (Belau). Eastern Pacific: from Aleutian Islands, USA, to Baja California, Mexico, also Chile.
Habitat and Biology:
Marine and benthic or pelagic, on the continental and insular shelves and upper slopes, depths from surface to at least 1875 m. Young often close inshore, adults often in deeper water below 91 m. A mostly deepwater shark, sluggish but strong-swimming; found near and well off the bottom. Captive individuals become greatly disturbed at even moderately high light levels, indicating a great sensitivity to light at very low levels. Large individuals offer little resistance when captured, but small ones may snap and thrash vigorously. It may sit on the bottom by day, and rise to the surface at night to feed. Feeds on a wide range of marine organisms, including other sharks (known to attack hooked conspecifics, sometimes following them up to the surface from deep water), rays, chimaeras, many types of bony fishes including dolphinfishes, small swordfish and marlin, herring, grenadiers, cod, ling, hake, flounders, gurnards and anglers, as well as squids crabs; shrimp, carrion, and even seals. Ovoviviparous, litters very large, 22 to 108. Not known to have attacked people without provocation; young will snap when captured.
Size:
Maximum total length at least 482 cm, females mature at about 450 to 482 cm, size at birth about 65 to 70 cm.
Interest to Fisheries:
Locally common and taken by line gear, gillnets, traps and pelagic and bottom trawls; utilized fresh, frozen, dried salted for human consumption, and for fishmeal and oil.
Remarks:
I follow Springer and Waller (1969) in including Hexanchus corinus in synonymy of H. griseus. The account of H. griseus australis by De Buen (1960) indicates that this subspecies differs from typical H. griseus in having only 5 rows of large, comblike anterolateral teeth on each side of the lower symphysis and a more elongated, more prominent ventral caudal lobe (H. griseus with 6 rows of comblike lower anteral teeth on each side and with a weak ventral caudal lobe). H. vitulus also differs from typical H. griseus in having a stronger ventral caudal lobe and only 5 rows of comblike lower anterolateral teeth, but other descriptive information and measurements in De Buen (1960) indicate that H. griseus australis has fin and body proportions and lower teeth otherwise similar to typical H. griseus rather than H. vitulus. The taxonomic position of H. griseus australis is dubious at present, because the holotype of this subspecies and other De Buen species from deep water off Chile were apparently lost (J.D. McEachran, pers.comm.). I have been unable to examine Hexanchus material from Chile and tentatively rank H. griseus australis in synonymy of H. griseus without recognizing it as a subspecies.
Type material:
Holotype: Unknown. Type Locality: Mediterranean Sea.