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The torpedo scad, ''Megalaspis cordyla'' (also known as the hardtail scad, finny scad, finletted mackerel scad and cordyla scad), is a species of moderately large marine fish classified in the jack and horse mackerel family, Carangidae. The torpedo scad is distributed throughout the tropical Indo-Pacific region, ranging from South Africa in the west to Tonga in the east, extending to Japan in the north and Australia in south. It is a schooling pelagic fish which occupies the surface layers of both inshore and offshore oceanic waters. The torpedo scad is easily identified by both its 'torpedo' shaped body and a series of detached finlets at the rear of both the dorsal and anal fins. The largest recorded individual was 80 cm long and weighed 4 kg, although it is more common at lengths less than 40 cm. It is a predatory species, taking a variety of fish, cephalopods and crustaceans by both active and filter feeding. There is a shift in diet as the species grow; however fish is the dominant prey in all size classes. Torpedo scad reach sexual maturity at 22 cm in females and 26.4 cm in males, with spawning occurring between March and July in India, where significant research into larval growth and morphometrics has been carried out. The torpedo scad is of major importance to fisheries throughout the Indo-Pacific, including India. Statistics (which exclude India) show the annual catch of the species has risen from 70 000 t in 1997 to 107 000 t in 2007. The major users of the species from this data are Indonesia and Malaysia. The torpedo scad is often taken by anglers, however it is considered only marginal table fare and is occasionally used as bait. ==Taxonomy and phylogeny== The torpedo scad is the only member of the monotypic genus ''Megalaspis'', which is one of the thirty genera in the family Carangidae, a group of perciform fishes in the suborder Percoidei. The species was first scientifically described by Carl Linnaeus, a famed Swedish naturalist who is widely considered the father of modern taxonomy. The specimen described by Linnaeus was erroneously described as being from "America", and no holotype is known for the species. Ronald Frick designated a neotype for the species in 1999, however this was rejected as it failed to satisfy ICZN regulations. Linnaeus named the species ''Scomber cordyla'', placing the fish in the true mackerel genus, which was a common practice before the family Carangidae was recognised. The specific epithet is Latin for "mackerel" or "young tunny (tuna)". A second independent renaming of the species occurred in 1793 by Marcus Elieser Bloch, who assigned the name ''Scomber rottleri'', with several later redescriptions and namings occurring up until 1874.〔 In 1851 Pieter Bleeker reassigned ''Scomber rottleri'' to its own genus ''Megalaspis'', meaning "large scutes". When ''S. rottleri'' was found to be a junior synonym of ''S. cordyla'', the name of the species was finally transferred to ''Megalaspis cordyla'' where it has remained. ''M. cordyla'' has a variety of common names, the most common of which is 'torpedo scad', with 'hardtail scad', 'finny scad', 'finletted mackerel scad' and 'cordyla scad' occasionally used. Because of the wide range of the species, it has a large collection of non-English common names also. The relationship of the species to other carangids was assessed in Soko Gushiken's 1986 paper on the phylogeny of the Carangidae. It was the sole species in one of three distinct clades within the tribe Carangini. The torpedo scad has not been included in any later genetic phylogenetic studies of the Carangidae. 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「Torpedo scad」の詳細全文を読む スポンサード リンク
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