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The Irrawaddy dolphin (''Orcaella brevirostris'') is a euryhaline species of oceanic dolphin found in discontinuous subpopulations near sea coasts and in estuaries and rivers in parts of the Bay of Bengal and Southeast Asia. ==Etymology and taxonomic history== One of the earliest recorded descriptions of the Irrawaddy dolphin was by Sir Richard Owen in 1866 based on a specimen found in 1852, in the harbour of Visakhapatnam on the east coast of India.〔 It is one of two species in its genus. It has sometimes been listed variously in a family containing just itself and in Monodontidae and in Delphinapteridae. There is now widespread agreement to list it in the Delphinidae family. Genetically, the Irrawaddy dolphin is closely related to the killer whale (orca). It is also closely related to the Australian snubfin dolphin, and these two were only recently recognised as distinct species. The species name ''brevirostris'' comes from the Latin meaning short-beaked. In 2005, genetic analysis showed the Australian snubfin dolphin found at the coast of northern Australia forms a second species in the ''Orcaella'' genus. Overall, the dolphins' colour is grey to dark slate blue, paler underneath, with no distinctive pattern. The dorsal fin is small and rounded behind the middle of the back. The forehead is high and rounded; the beak is lacking. The front of its snout is blunt. The flippers are broad and rounded. The species found in Borneo, the finless porpoise, ''Neophocaena phocaenoides'', is similar and has no back fin; the humpback dolphin, ''Sousa chinensis'', is larger, has a longer beak and a larger dorsal fin.〔 Vernacular names for ''O. brevirostris'' include the following: *Burmese: ဧရာဝတီ လင်းပိုင် ''eyawadi lăbaing'' *Chilika dialect: ''baslnyya magar'' or ଭୂଆଷୁଣୀ ମଗର ''bhuasuni magar'' (lit. oil-yielding dolphin) *Filipino: ''lampasut'' *Bangladesh: ''shushuko'' *Indonesian: ''pesut'' *Khmer: ផ្សោត ''ph’sout'' *Lao: ປາຂ່າ ''pha’ka'' *Malay: ''dolphin empesut'' *Odia: ଖେମ ''khem'' or ଖେରା ''khera'' *Thai: โลมาอิรวดี ''pla loma hua bat'' ("alms-bowl dolphin", due to the shape of their heads)〔 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「Irrawaddy dolphin」の詳細全文を読む スポンサード リンク
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