Thunnus thynnus

Author: (Linnaeus, 1758)

Thunnus thynnus (Linnaeus, 1758)

Status in World Register of Marine Species:
Accepted name: Thunnus thynnus (Linnaeus, 1758) (updated 2009-06-25)

Diagnosis: a very large species with a fusiform and rounded body (nearly circular in cross-section), very robust in front. Gillrakers 34-43 on first arch. Pectoral fins very short, less than 80% of head length, never reaching the inter-space between the dorsal fins. Ventral surface of liver striated. Colour: lower sides and belly silvery-white with colourless transverse lines alternating with rows of colourless dots (the latter dominate in older fish), visible only in fresh specimens; first dorsal fin yellow or bluish, the second reddish-brown; anal fin and finlets dusky yellow edged with black; lateral keel black in adults. Size: to over 300 cm fork length, 560 kg, common to 200 cm.

Habitat: epi- and mesopelagic, immature in warm waters, adults also entering cold waters. Fast swimming, effecting transoceanic migrations, young schooling. Food: many kinds of fishes, crustaceans and cephalopods. Reproduction: does not breed in northern waters. Eggs and larvae have been reported from the Mediterranean in June and July and from off south-western Spain in June.

Distribution: from the Canaries and the Azores north to Ireland, the North Sea, and the coast of Norway. Occasionally reaches Iceland and Murmansk. Found in the Mediterranean Sea and the southern part of the Black Sea.

Eggs, larvae and young stages. Ehrenbaum, 1924: 25, fig. 5a-5f (larvae) (?) | Sanzo, 1929: 104 (eggs and larvae) | Soljan, 1948 (transl. 1963): 149, fig. p. 149 (juv.) | Bellon, 1954: 56 (eggs and larvae) | Padoa, 1956: 491, fig. 323-324 (eggs), 325-332 (larvae), 333 (juv.), 334 (Th. brachypterus = young specimen of Th. thynnus) | Tiews, 1963: 450, fig. p. 452 (eggs) | Bini, 1968, 6: 48, 2 fig.
Otoliths (sagitta). Bellon, 1954: 26 | Chaine, 1957: 492, pl. 3.


Thunnus thynnus thynnus: the north Atlantic subspecies which is replaced by Thunnus thynnus orientalis in the North Pacific.