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Hector's dolphin (''Cephalorhynchus hectori'') is the best-known of the four dolphins in the genus ''Cephalorhynchus'' and is found only in New Zealand. At approximately 1.4 m in length, it is one of the smallest cetaceans, and New Zealand's only endemic cetacean. Two subspecies occur: ''C. h. hectori'', the more numerous subspecies, is found around the South Island, and the critically endangered Maui's dolphin (''C. h. maui'') is found off the northwest coast of the North Island. Maui's dolphin is one of the eight most endangered groups of cetaceans. The Hector's dolphin is also the world's smallest and rarest dolphin.〔"Hector's Dolphin." WorldWildlife.org. World Wildlife Fund, n.d. Web. 23 Oct. 2014.〕 A 2010/2011 survey of Maui's dolphin by the New Zealand Department of Conservation estimated only 55 adults remained. Hector’s dolphin was named after Sir James Hector (1834–1907), who was the curator of the Colonial Museum in Wellington (now the Museum of New Zealand Te Papa Tongarewa). He examined the first specimen found of the dolphin. The species was scientifically described by Belgian zoologist Pierre-Joseph van Beneden in 1881. Māori names for Hector's and Maui's dolphin include ''tutumairekurai, tupoupou'' and ''popoto''. ==Description== Hector’s dolphin is the smallest of the dolphins. Mature adults have a total length of and weigh .〔Slooten, E. and Dawson, S.M. 1994. Hector’s dolphin ''Cephalorhynchus hectori''. Pp. 311-333 in: Handbook of Marine Mammals. Volume V (Delphinidae and Phocoenidae) (S.H. Ridgway and R. Harrison eds). Academic Press. New York.〕 The species is sexually dimorphic, with females being slightly longer and heavier than males. The body shape is stocky, with no discernible beak. The most distinctive feature is the rounded dorsal fin, with a convex trailing edge and undercut rear margin. The overall appearance is pale grey, but closer inspection reveals a complex and elegant combination of colours. The back and sides are predominantly light grey, while the dorsal fin, flippers, and flukes are black. The eyes are surrounded by a black mask, which extends forward to the tip of the rostrum and back to the base of the flipper. A subtly shaded, crescent-shaped black band crosses the head just behind the blowhole. The throat and belly are creamy white, separated by dark-grey bands meeting between the flippers. A white stripe extends from the belly onto each flank below the dorsal fin. At birth, Hector’s dolphin calves have a total length of and weigh .〔Slooten, E. 1991. Age, growth and reproduction in Hector’s dolphins. Canadian Journal of Zoology 69: 1689-1700.〕 Their coloration is the same as adults, although the grey has a darker hue. Four to six vertical pale stripes, caused by fetal folds affecting the pigmentation, are present on the calf’s body until an age of about six months. 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「Hector's dolphin」の詳細全文を読む スポンサード リンク
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