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The grass carp (''Ctenopharyngodon idella'') is a herbivorous, freshwater fish species of the family Cyprinidae, and the only species of the genus ''Ctenopharyngodon''. It is a large cyprinid native to eastern Asia, with a native range from northern Vietnam to the Amur River on the Siberia-China border.〔Mandrak and Cudmore. 2004. (''Biological Synopsis of Grass Carp (Ctenopharyngodon idella)'' ).〕 It is cultivated in China for food, but was introduced in Europe and the United States for aquatic weed control. It is a fish of large, turbid rivers and associated floodplain lakes, with a wide degree of temperature tolerance. Grass carp will enter reproductive condition and spawn at temperatures of 20 to 30°C (68 to 86°F).〔〔Shireman, J.V. and C.R. Smith. 1983. ''Synopsis of biological data on the grass carp, Ctenopharyngodon idella (Cuvier and Valenciennes, 1844)''. Food and Aquaculture Organization Synopsis. 135: 86pp.〕 In the United States, the fish is also known as white amur, which is derived from the Amur River, where the species is probably native, but has never been abundant.〔 This is not to be confused with the white Amur bream (''Parabramis pekinensis''), which is not a particularly close relative. For eating, the fish may be steamed, pan-fried, broiled, or baked.〔 ==Appearance and anatomy== Grass carp have elongated, chubby, torpedo-shaped body forms. The terminal mouth is slightly oblique with non-fleshy, firm lips, and no barbels.〔(''Grass carp'' ) in ''fishbase.org''.〕 The complete lateral line contains 40 to 42 scales. Broad, ridged, pharyngeal teeth are arranged in a 2, 4-4, 2 formula. The dorsal fin has eight to 10 soft rays, and the anal fin is set closer to the tail than most cyprinids. Body color is dark olive, shading to brownish-yellow on the sides, with a white belly and large, slightly outlined scales. The grass carp grows very rapidly. Young fish stocked in the spring at will reach over by fall. The average length is about 60–100 cm (24–39 in). The maximum length is 1.4 m (4.6 ft) and the maximum weight 40 kg (88 lb). According to one study, they live an average of five to 9 years, with the oldest surviving 11 years.〔Kirk and Socha. (''Longevity and Persistence of Triploid Grass Carp Stocked into the Santee Cooper Reservoirs of South Carolina'' ). J. Aquat. Plant Manage. 41:2003.〕 They eat up to three times their own body weight daily. They thrive in small lakes and backwaters that provide an abundant supply of freshwater vegetation. 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「Grass carp」の詳細全文を読む スポンサード リンク
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