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:''This species is sometimes called the leopard shark, a name otherwise used for ''Triakis semifasciata. The zebra shark (''Stegostoma fasciatum'') is a species of carpet shark and the sole member of the family Stegostomatidae. It is found throughout the tropical Indo-Pacific, frequenting coral reefs and sandy flats to a depth of . Adult zebra sharks are distinctive in appearance, with five longitudinal ridges on a cylindrical body, a low caudal fin comprising nearly half the total length, and a pattern of dark spots on a pale background. Young zebra sharks under long have a completely different pattern, consisting of light vertical stripes on a brown background, and lack the ridges. This species attains a length of . Zebra sharks are nocturnal and spend most of the day resting motionless on the sea floor. At night, they actively hunt for molluscs, crustaceans, small bony fishes, and possibly sea snakes inside holes and crevices in the reef. Though solitary for most of the year, they form large seasonal aggregations. The zebra shark is oviparous: females produce several dozen large egg capsules, which they anchor to underwater structures via adhesive tendrils. Innocuous to humans and hardy in captivity, zebra sharks are popular subjects of ecotourism dives and public aquaria. The World Conservation Union has assessed this species as Vulnerable worldwide, as it is taken by commercial fisheries across most of its range (except off Australia) for meat, fins, and liver oil. There is evidence that its numbers are dwindling. ==Taxonomy== The zebra shark was first described as ''Squalus varius'' by Seba in 1758. No type specimen was designated, though Seba included a comprehensive description in Latin and an accurate illustration of a juvenile. Müller and Henle placed this species in the genus ''Stegostoma'' in 1837, using the specific epithet ''fasciatus'' (or the neuter form ''fasciatum'', as ''Stegostoma'' is neuter while ''Squalus'' is masculine) from an 1801 work by Bloch and Schneider. In 1984, Compagno rejected the name "varius/m" in favor of "fasciatus/m" for the zebra shark, because Seba did not consistently use binomial nomenclature in his species descriptions (though ''Squalus varius'' is one that can be construed as a binomial name). In Compagno's view, the first proper usage of "varius/m" was by Garman in 1913, making it a junior synonym.〔Martin, R.A. (January 31, 1999). (Albino Zebras and Leopards Changing Their Spots ). ReefQuest Centre for Shark Research. Retrieved on May 12, 2009.〕 Both ''S. fasciatum'' and ''S. varium'' are currently in wide usage for this species.〔 The genus name is derived from the Greek ''stego'' meaning "covered", and ''stoma'' meaning "mouth".〔Bester, C. (Biological Profiles: Zebra Shark ). Florida Museum of Natural History Ichthyology Department. Retrieved on May 12, 2009.〕 The specific epithet ''fasciatum'' means "banded", referring to the striped pattern of the juvenile. The juvenile coloration is also the origin of the common name "zebra shark". The name "leopard shark" is sometimes applied to the spotted adult, but that name usually refers to the houndshark ''Triakis semifasciata'', and is also sometimes used for the tiger shark (''Galeocerdo cuvier'').〔 Due to their different color patterns and body proportions, both juveniles and subadults have historically been described as separate species (''Squalus tigrinus'' and ''S. longicaudatus'' respectively).〔 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「Zebra shark」の詳細全文を読む スポンサード リンク
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