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The false scad, ''Caranx rhonchus'' (also known as the spotfin scad, ten-finned horse mackerel and yellow horse mackerel), is a species of medium-sized marine fish classified in the jack family Carangidae. The false scad is distributed throughout the tropical and temperate waters of the eastern Atlantic Ocean from Namibia in the south to Spain and throughout most of the Mediterranean in the north. The species has an atypical body form compared to other species of ''Caranx'', and can be distinguished from these on its elongate 'scad-like' body shape alone. Distinguishing the species from members of ''Decapterus'' and ''Trachurus'' is more difficult, requiring detailed anatomical analysis. The false scad is known to grow to a length of 60 cm and a weight of 1 kg. The species lives both pelagically and demersally in continental shelf waters, ranging from depths of 15 to 200 m. It is a predatory fish, taking small fishes, crustaceans including euphausiids and shrimps, and cephalopods as its main prey, with significant dietary shifts as it ages. The false scad reaches sexual maturity at 2 years of age, with spawning occurring between April and July in shallow inshore waters, where the juveniles remain. The species is of major importance to fisheries throughout its range, but particularly from Morocco to Senegal, with annual catches ranging from 500 to 19000 t. The species is caught using trawls, seine nets and gill nets and sold fresh, frozen or salted. ==Taxonomy and naming== The false scad 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. The species was first scientifically described by the French naturalist Étienne Geoffroy Saint-Hilaire in 1817 based on a specimen from Alexandria, Egypt which was designated to be the holotype. He named the species ''Caranx rhonchus'', with the specific epithet of Latin origin meaning 'snorting' or 'croaking', in reference to the sound the species often makes when pulled from the water. The species placement in ''Caranx'' was later revised to ''Decapterus'', although the revision was not accepted by all authors with the generic status of the species undetermined for many years. It has now been accepted by most taxonomic authorities, that despite the species appearance, the false scad shares more anatomical features with ''Caranx'' than ''Decapterus''. The species was independently renamed once by Henry Weed Fowler in 1919 under the name of ''Caranx angolensis'', which was similarly shifted to ''Decapterus'' before synonymy was recognized and the name sunk into ''C. rhonchus''. The common name of 'false scad' refers to the scad like appearance of the fish, despite it not being a member of ''Decapterus'' or ''Trachurus'', the two genera most commonly referred to as 'scads'. Other lesser used names for the species include spotfin scad, ten-finned horse mackerel and yellow horse mackerel.〔 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「False scad」の詳細全文を読む スポンサード リンク
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