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:''Not to be confused with the blacktip reef shark, ''Carcharhinus melanopterus''.'' The blacktip shark (''Carcharhinus limbatus'') is a species of requiem shark, and part of the family Carcharhinidae. It is common to coastal tropical and subtropical waters around the world, including brackish habitats. Genetic analyses have revealed substantial variation within this species, with populations from the western Atlantic Ocean isolated and distinct from those in the rest of its range. The blacktip shark has a stout, fusiform body with a pointed snout, long gill slits, and no ridge between the dorsal fins. Most individuals have black tips or edges on the pectoral, dorsal, pelvic, and caudal fins. It usually attains a length of . Swift, energetic piscivores, blacktip sharks are known to make spinning leaps out of the water while attacking schools of small fish. Their demeanor has been described as "timid" compared to other large requiem sharks. Both juveniles and adults form groups of varying size. Like other members of its family, the blacktip shark is viviparous; females bear 1–10 pups every other year. Young blacktip sharks spend the first months of their lives in shallow nurseries, and grown females will return to the nurseries where they were born to give birth themselves. In the absence of males, females are also capable of asexual reproduction. Normally wary of humans, blacktip sharks can become aggressive in the presence of food and have been responsible for a number of attacks on people. This species is of importance to both commercial and recreational fisheries across many parts of its range, with its meat, skin, fins, and liver oil used. It has been assessed as Near Threatened by the International Union for Conservation of Nature (IUCN), on the basis of its low reproductive rate and high value to fishers. ==Taxonomy== The blacktip shark was first described by French zoologist Achille Valenciennes as ''Carcharias (Prionodon) limbatus'' in Johannes Müller and Friedrich Henle's 1839 ''Systematische Beschreibung der Plagiostomen''. The type specimens were two individuals caught off Martinique, both of which have since been lost. Later authors moved this species to the genus ''Carcharhinus''.〔Curtis, T. (Biological Profiles: Blacktip Shark ). ''Florida Museum of Natural History Ichthyology Department''. Retrieved on April 27, 2009.〕 The specific epithet ''limbatus'' is Latin for "bordered", referring to the black edges of this shark's fins. Other common names used for the blacktip shark include blackfin shark, blacktip whaler, common or small blacktip shark, grey shark, and spotfin ground shark.〔 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「blacktip shark」の詳細全文を読む スポンサード リンク
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