Common Name
Yellowfin Tuna
Year Described
Bonnaterre, 1788
Identification
Dorsal Fin: XIII-XIV, 12-16, followed by 8-10 finlets
Anal Fin: 11-16, followed by 7-10 finlets
Pectoral Fin: 30-36
Gill Rakers: 26-34 (on first arch)
Vertebrae: 39
Body fusiform, robust, and oval in cross-section. Snout about twice eye diameter. Adipose eyelid absent. Jaw extends to anterior half of orbit. Teeth small and conical. Two interpelvic processes; shorter than pelvic fins. Dorsal fins separated by a very small gap. Spiny dorsal fin long, with a strongly concave margin. Second dorsal and anal fin with very tall anterior lobes (up to 20% of FL in large fish). Pectoral fins long (reaching to second dorsal fin but never beyond its rearmost ray). Caudal fin semilunate. Corselet not obvious but present. Body covered in very small scales. Two small caudal keels with a larger median keel in between them. No striations on liver.
Color
Body white with an abruptly dark blue back. A strong golden sheen on the flanks often forms a diffuse stripe from snout to caudal fin. Sometimes with thin vertical lines on the ventral surface. Dorsal and anal fins and finlets golden. Pectoral and caudal fin dusky to yellowish.
Size
Maximum size to 240cm FL. Common to 150cm FL.
Habitat
Epipelagic in oceanic waters. Forms large schools.
Range
Nova Scotia to S. Brazil, including the Gulf of Mexico and the Caribbean Sea.
References
Collette, B.B. 2002. Scombridae (pp 1836-1857). In: Carpenter. 2002. The living marine resources of the Western Central Atlantic. Vol. 3: Bony fishes part 2 (Opistognathidae to Molidae), sea turtles and sea mammals. FAO Species Identification Guides for Fisheries Purposes. American Society of Ichthyologists and Herpetologists Special Publication No. 5.
McEachran, J.D. and J.D. Fechhelm. 2005. Fishes of the Gulf of Mexico. Volume 2: Scorpaeniformes to Tetraodontiformes. University of Texas Press, Austin. i-viii +1-1004.