Author: (Linnaeus, 1758)
Field Marks:
A usually unspotted, large Mustelus with a short head and snout, broad internarial space, large eyes, narrow interorbital space, upper labial furrows slightly longer than lowers, low-crowned teeth with weak cusps, buccopharyngeal denticles confined to extreme front of mouth, lateral trunk denticles usually lanceolate and with complete ridges, unfringed dorsal fins, 70 to 93 precaudal centra, and a semifalcate ventral caudal lobe. It is the only smooth-hound with the above characters where it occurs.
Diagnostic Features:
Body fairly slender head short, prepectoral length 17 to 21% of total length; snout moderately long and bluntly angular in lateral view, preoral sno. 5.3 to 7.4% of total length, preorbital snout 5.9 to 8% of total length; internarial space broad, 2.4 to 3% of total ler-'h; eyes fairly large, eye length about 1.9 to 2.8 times in preorbital snout and 2.3 to 4% of total length; interorbital space narrow, 3.7 to 4.8% of total length; mouth fairly short, length subequal to eye length and 2.2 to 3.5% of total length; upper labial furrows usually slightly longer than lowers and 1.4 to 2.1% of total length; teeth molariform and asymmetric, with cusp reduced to a low point, cusplets absent except in very young sharks; buccopharyngeal denticles confined to tongue tip and extreme anterior end of palate. Interdorsal space 18 to 25% of total length; trailing edges of dorsal fins denticulate, without bare ceratotrichia; first dorsal falcate, with posterior margin almost vertical, midbase closer to pectoral bases than pelvics; pectoral fins moderately large, length of anterior margins 13 to 17% of total length, width of posterior margins 8.2 to 14% of total length; pelvic fins moderately large, anterior margin 6.5 to 9.9% of total length; anal height 2.4 to 4.3% of total length; anal caudal space greater than second dorsal height, and 6.3 to 8.8% of total length; ventral caudal lobe more or less falcate in adults. Crowns of lateral trunk denticles lanceolate or weakly tricuspidate, with longitudinal ridges extending their entire length. Cranium and hyomandibulae not hypercalcified in adults, but scapulocoracoid tips, distal pectoral radials, and hypochordal arches sometimes slightly hypercalcified; palatoquadrates not subdivided; monospondylous precaudal centra 25 to 32, diplospondylous precaudal centra 40 to 66, precaudal centra 70 to 93. Colour uniform grey or grey-brown, above, light below, no white spots or dark bars, some specimens with dark spots. Development viviparous. Size large, adults 70 to at least 164 cm.
Geographical Distribution:
Eastern Atlantic: France and British Isles to Mediterranean, Morocco, Canary Islands, Madeira, Angola, South Africa.
Habitat and Biology:
An abundant shark of the continental shelves and uppermost slopes, most commonly found in shallow water at depths from 5 to 50 m, but often in the intertidal region and ranging to at least 350 m depth; sometimes in midwater but prefers to swim near the bottom.
Viviparous, with a yolk-sac placenta; number of young 4 to 15 per litter. Gestation period about 10 to 11 months.
Primarily a crustacean feeder that eats crabs, lobsters, slipper lobsters, hermit crabs, and shrimps, but also cephalopods (including octopi) and bony fishes (including snake eels). A deep-caught individual (300 m) had a midwater fish (greeneye, Chlorophthalmus) in its stomach.
Size:
Maximum 164 cm, males maturing between 70 and 74 cm and reaching at least 110 cm, females maturing at about 80 cm and reaching at least 164 cm. Size at birth about 39 cm.
Interest to Fisheries:
Fisheries exist for this species in European waters, the Mediterranean, and off West Africa: this shark is very common and is taken in bottom trawls, fixed bottom nets, with line gear, and occasionally even in pelagic trawls. It is utilized fresh and fresh-frozen for human consumption (France, Federal Republic of Germany, Italy), also dried salted and smoked; its liver is used for oil and carcasses for fishmeal. In South Africa, it is commonly taken by sportsfishers from shore on sandy beaches.
Remarks:
This species is very close to M. canis of the western Atlantic and has been sometimes confused with it, but, according to Heemstra (1973), it differs in having somewhat shorter upper labial furrows, a narrower internarial, and fewer vertebrae.
Type material:
Holotype: None. Type Locality: "Habitat in Europa".