Lamna nasus

Author: (Bonnaterre, 1788)

Lamna nasus (Bonnaterre, 1788)

Status in World Register of Marine Species:
Accepted name: Lamna nasus (Bonnaterre, 1788) (updated 2009-06-25)

Diagnosis: body fusiform, trunk robust; snout conical, pointed upper jaw slightly protusible; teeth with edges smooth, in the form of an awl, with lateral basal cusplets, the first 2 teeth in each jaw similar in form to those succeeding, the third upper tooth smaller than second or fourth, the third lower tooth about equal to fourth. First dorsal fin origin above or anterior to inner corner of pectoral fins; second dorsal fin origin over origin of anal. Caudal peduncle very strongly flattened and widely expanded laterally; a secondary longitudinal keel, less distinct, below main keel on caudal peduncle. Colour: dark blue or bluish-grey above, white or pale cream on flanks and belly; outer half or third of pectoral fins dusky; anal white or slightly dusky. Size: to over 3 m (possibly 3.7 m), usually males 2.6 m, females 2.2 m.

Habitat: epipelagic, coastal and oceanic, mostly found in deep midwaters at 200-700 m, but also occurring on or near the surface; very common. Food: wide range of pelagic and demersal fishes. Reproduction: ovoviviparous; the young are few (up to four) and their size at birth 50-75 cm.

Distribution: eastern Atlantic, from Morocco to Iceland and western Barents Sea, also Mediterranean. Elsewhere, western Atlantic and temperate waters of Southern Hemisphere (Atlantic, Pacific and Indian Oceans).

Eggs, larvae and young stages. Calderwood 1887: 263 (embryos) | Collett 1905: 77 (embryos) | Swenander, 1907 (embryonic development) | Shann 1911: 73 ; 1923: 161 (embryos) | Hubbs, 1923 (large embryo, Maine) | Nordgaard 1939: 39 (embryos) | Bigelow and Schröder 1948 :116, fig. 17 (embryos) | Aasen, 1965 (growth).