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''Conocephalus discolor'', the long-winged conehead, is a member of the family Tettigoniidae . This bush-cricket is native to the British Isles and is considered a nationally scarce species.〔(【引用サイトリンク】url=http://www.orthoptera.org.uk/account.aspx?ID=17 )〕 This species can be easily confused with the short-winged conehead (''Conocephalus dorsalis''), a close relative. These two species are phenotypically similar; however, the distinguishing factor between the two is the fully developed set of wings the long-winged conehead possesses that allows for flight. In the short-winged coneheads the hind wings are shorter than the abdomen, causing the wings to be vestigial and the species is incapable of flight.〔(【引用サイトリンク】title=British insects: the genera of Orthoptera )〕 For this reason it is hard to discriminate between the two species during the early stages of their life cycle before the wings have fully developed. The colouration of the conehead is typically a grass green, though there are some brown phenotypes, with a distinctive brown stripe down its back. ==Description== The body of bush-crickets is covered by a protective exoskeleton and is divided into three parts: the head, thorax, and abdomen. The topmost segment of the thorax, the pronotum, is shaped like a saddle and is primarily used for protection. Bush-crickets are also equipped with large hind legs for jumping and biting mouth parts for grip and protection. The phenotypic aspects that are characteristic to this family of insects are the antennae, which typically exceed the length of their body, and the straight sword shaped ovipositor that the females use for laying eggs.〔 The body of ''C. discolor'' is when it reaches maturity.〔(【引用サイトリンク】title=The Overlooked Orthoptera: an introduction to grasshoppers and bush-crickets )〕 Its hind wings are longer than its forewings and they both reach beyond the tip of the abdomen. A distinctive dorsal stripe runs down the thorax, covering its head and pronotum, which is long. Adults have a slender grass green body, brown wings, brown ovipositor, a reddish brown abdomen, and a dark brown stripe that edges white near the thorax. Nymphs differ slightly in colouration with a light green body and a white margined black stripe.〔 ''C. discolor'' is a wing polymorphic species. Most wing-dimorphic tettigoniids have a brachypterous (short-winged) form and a macropterous (long-winged) form. However, since ''C. discolor'' is already considered a long winged species, its alternative form is extra long winged, with wing lengths up to a third longer than normal individuals. An experiment performed by Ando and Hartley in 1982 on the embryonic development of this species provided evidence that the tendency for an individual to develop as one wing morph or the other is dependent on the density of the population. In this species the development of individuals with extra long wings is induced by crowding. Wing dimorphism does not only affect wing length, but also affects flight, dispersal, and reproductive capability of this species. The juvenile hormone is responsible for wing polymorphism in orthoptera and has also been known to play a role in the trade-off between wing morphology and reproductive capability. 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「Conocephalus discolor」の詳細全文を読む スポンサード リンク
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