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The bigeye trevally, ''Caranx sexfasciatus'' (also known as the bigeye jack, great trevally, six-banded trevally and dusky jack), is a species of widespread large marine fish classified in the jack family Carangidae. The bigeye trevally is distributed throughout the tropical waters of the Indian and Pacific Oceans, ranging from South Africa in the west to California and Ecuador in the east, including Australia to the south and Japan in the north. The bigeye trevally is best distinguished by its colouration, having a dark second dorsal fin with a white tip on the lobe, and also possessing a small dark spot on the operculum. Other more detailed anatomical features also set the species apart from other members of ''Caranx''. The species is known to grow to a length of 120 cm and 18 kg. It is predominantly an inshore fish, inhabiting reefs down to depths of around 100 m in both coastal zones and offshore islands, often venturing into estuaries and sandy bays as juveniles. The bigeye trevally is commonly found in large slow moving schools during the day, becoming active at night when it feeds, taking a variety of fish, crustaceans, cephalopods and other invertebrates. The fish is known to move from a more crustacean dominated diet as a juvenile to a nearly completely fish dominated diet as an adult. Sexual maturity is reached at 42 cm, with spawning occurring in large aggregations occurring at different periods throughout its range, generally between July and March. The bigeye trevally is of moderate importance to fisheries throughout its range, and being of high importance to some artisanal fisheries. It is taken by gill net, purse seine, hook and line and other artisanal fishing methods. It is rated as a fair to good table fish. The species is also considered a good gamefish, taken by lure, bait and spear throughout its range. ==Taxonomy and naming== The bigeye trevally is classified within the genus ''Caranx'', one of a number of groups known as the jacks or trevallies. ''Caranx'' itself is part of the larger jack and horse mackerel family Carangidae, a group of percoid fishes in the order Perciformes. Prior to its description in 1825, the species was often confused with the similar-looking Atlantic species ''Caranx hippos'', and its synonym ''Caranx carangus''. The species was first properly scientifically described by the French naturalists Jean René Constant Quoy and Joseph Paul Gaimard in 1825 from a specimen collected off Waigeo, Indonesia which was designated to be the holotype. They named the species ''Caranx sexfasciatus'' which the species is still currently accepted as, with the specific epithet meaning 'six banded' in relation to its juvenile colouration. Following this, the species was independently redescribed and named around fifteen times, and incorrectly broken into two subspecies. In his massive ichthyological volume entitled ''Histoire Naturelle des Poissons'', Georges Cuvier managed to assign no less than four junior synonyms to the species, while the most recent renaming was by Yojiro Wakiya in 1924, who applied the name ''Caranx oshimai''. The two subspecies proposed were ''Caranx sexfaciatus elacate'' and ''Caranx sexfaciatus marginatus'', both based on prior descriptions by Jordan and Evermann, and Gill respectively.〔 All names except ''Caranx sexfasciatus'' are considered junior synonyms under ICZN rules and discarded. The common name preferred by most authorities is 'bigeye trevally', 'bigeye kingfish', 'bigeye crevalle jack' or bigeye jack', with other names used including 'great trevally', 'six-banded trevally' and 'dusky jack'.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Bigeye trevally」の詳細全文を読む スポンサード リンク
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