Odontaspis ferox

Author: (Risso, 1810)

Field Marks:
A large, bulky shark with a long, bulbously conical snout, eyes moderately large, without nictitating eyelids, mouth long and extending behind eyes, teeth moderately large, with prominent narrow cusps and 2 or more pairs of lateral cusplets, upper anterior teeth separated from lateral teeth by 3 to 5 rows of small intermediate teeth. Anal fin and second dorsal fin smaller than first dorsal but broadbased, first dorsal fin on back and closer to pectoral fins than pelvics, upper precaudal pit present but lateral keels absent from caudal peduncle, caudal fin asymmetrical but with a strong ventral lobe. Colour: medium grey, sometimes with darker reddish spots scattered on body.

Diagnostic Features:
Teeth mostly with 2 or 3 pairs of lateral cusplets, root lobes deeply arched and narrow; 3 to 5 rows of small intermediate teeth between upper anterior and lateral tooth rows. First dorsal fin with its posterior margin sloping posteroventrally from its apex; origin of second dorsal fin about over rear ends of pelvic bases; anal fin high and erect, height almost equal to base length; length of dorsal margin of caudal fin about 30% of total length in young. Colour: medium grey above, lighter below, young with black-tipped dorsal fins, some individuals with dark reddish spots.

Geographical Distribution:
Eastern North Atlantic: Gulf of Gascony, Madeira, Morocco, Mediterranean. Western Indian Ocean: South Africa, ? Madagascar. Western Pacific: Japan, Australia (New South Wales). Central Pacific: Hawaiian Islands. Eastern Pacific: Southern California, Gulf of California.

Habitat and Biology:
This shark is a little-known inhabitant of deepish water in warm-temperate and tropical seas, on or near the bottom on continental and insular shelves and upper slopes at depths of 13 to 420 m. Reproduction is unknown in the species, but presumably is similar to Eugomphodus taurus. It feeds on small bony fishes, squids and shrimps. Its teeth are noticeably smaller and less robust than those of E. taurus, suggesting that it takes smaller and possibly less active prey than the latter. Also, its dentition is more weakly differentiated along the jaws, with its lateral teeth less specialized for cutting than E. taurus and its posterior teeth not differentiated into specialized crushers; this suggests a more uniform diet of softer prey than in E. taurus. Probably its deepwater habitat does not allow this shark to regulate its buoyancy by gulping air as in E. taurus; it does, however, have a longer body cavity than E. taurus, with a very large, oily liver, and presumably uses this organ as its primary hydrostatic structure. It is not implicated in attacks on people.

Size:
Maximum total length about 360 cm, male mature at 275 cm, females to 360 cm, size at birth above 105 cm.

Interest to Fisheries:
This uncommon species is primarily taken in the Mediterranean Sea and off Japan with bottom gillnets, line gear, and bottom trawls. It is used for human food (its flesh is considered far inferior to that of Eugomphodus taurus in Japan) and for its liver, which is very large, oily and has a reasonably high squalene content.

Remarks:
Garrick (1974) recognized Odontaspis herbsti for members of the genus from New Zealand, Australia, California and Madeira that differed from the Mediterranean O. ferox only in lacking spots. This was followed by Bass, d'Aubrey and Kistnasamy (1975b) for South African spotless individuals, but Robins et al. (1980:69) noted that specimens from California may have spots or lack them. Apparently presence of spots is a matter of individual variation in what is here considered a single species O. ferox. Eugomphodus taurus is also variable in presence of spots.

Type material:
Holotype: Unknown. Type Locality: Off Nice, France, Mediterranean Sea.

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