Little tunny

The little tunny (Euthynnus alletteratus) is the most common tuna in the Atlantic Ocean. It is found in warm temperate and tropical waters of the Atlantic and the Mediterranean; in the western Atlantic, it ranges from Brazil to the New England states. It is found regularly in offshore and inshore waters, and is classified as a highly migratory species by UNCLOS. Occurring in large schools and weighing up to 36 lb, it is one of the smaller members of the tuna family (Scombridae). Commonly called bonita, false albacore, or little tuna, it resembles the Atlantic bonito, skipjack tuna, and species of mackerel. The little tunny feeds primarily on pelagic fish. It is best identified by the dark spots appearing between its pectoral and ventral fins and 'worm-like' markings on its back. Commercially, the fish is used as bait for sharks and marlin due to its high oil content and hook retention. It is considered by many to be a trash fish because it has a darker and stronger taste than that of the other tunas. However, the little tunny is commercially important in many locations, including the West Indies. It is marketed fresh, dried, canned, smoked, and frozen. It is sought-after as a sport fish due to its line-stripping 64 km/h (40 mph) runs and hard fighting ability when hooked. By trolling with lures near reefs, it can be caught on hook and line. Constantine Samuel Rafinesque identified the little tunny in 1810 and gave the fish its current name: Euthynnus alletteratus. Synonyms for used for the name include E. alleteratus alleteratus, E. alliteratus, E. thunina, and E. alletteratus aurolitoralis. The little tunny is not part of the genus Thunnus like many tuna, but it is part of the tribe Thunnini. The genus Euthynnus is derived from the Ancient Greek: εὖ, romanized: (eu), lit. 'good, well', and θύννος (thýnnos), 'tunny-fish' – which is in turn derived from θύνω (thynō), 'to rush; to dart'. The little tunny is small in body size compared to other tuna species. It has a compact and stream-lined body built to facilitate bursts of speed, as well as endurance while swimming. Its torpedo-shaped, robust body is made for powerful swimming. It has a large mouth with rigid jaws and a slightly protruding lower jaw, with a single row of small, inwardly curved, cone-shaped teeth on the palatines. Teeth are absent on the vomer, the small bone in the roof of the mouth, and the tongue has two longitudinal ridges. The snout is shorter than the rest of the head. The little tunny has a dorsal fin with 10 to 15 tall, descending spines, as well as a much smaller second dorsal fin followed by eight finlets. At the base, the two dorsal fins are separated by a small interspace. The anal fin has 11 to 15 slightly defined rays, and is followed by seven finlets. The pectoral fins are short and do not reach the end of the first dorsal fin and are joined to the pelvic fins by interpelvic processes. There are 37-45 gill rakers, bony projections off the gills, on the first arch. There are no scales on the body of the little tunny except along the lateral line and on the corselet: a thick band of scales circling the body. The coloration of the little tunny is typically metallic blue or blue-green with dark, wavy stripes above the lateral line. These 'worm-like' lines are within a well-marked border that never extends farther forward than the middle of the first dorsal fin. The belly is bright white with three to seven dark, fingerprint-like spots around the pectoral and pelvic fins. The little tunny is commonly confused with the Atlantic bonito because of coloration, but the two fish differ in their color patterns and overall body size. The little tunny's markings allow it to easily be distinguished from similar species. It is often confused with the skipjack tuna, the frigate tuna, the Atlantic bonito, and the bullet tuna. Close relatives also include the kawakawa and the black skipjack. The scattering of dark, fingerprint-like spots between the pectoral and pelvic fins cannot be found on any related Atlantic species. The first dorsal fin of the Atlantic bonito is also lower and sloping. Its lack of teeth on the vomer can set it apart from its close Pacific relatives, the kawakawa and the black skipjack. The dorsal fins of the bullet and frigate mackerel are set apart. Unlike the little tunny, the skipjack tuna lacks markings on the back and has broad, straight stripes on the underside.