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''Monachus'' is a genus containing the monk seals, a group of three pinniped species. They are the only earless seals that are found in tropical climates. They are now extremely rare, and the genus is in imminent danger of going entirely extinct, with only very limited genetic variation in the two surviving species. Fossils of the Mediterranean and Caribbean species are known from the Pleistocene. These include: * the Hawaiian monk seal, ''Monachus schauinslandi'' (critically endangered) * the Mediterranean monk seal, ''Monachus monachus'' (critically endangered) * the Caribbean monk seal, ''Monachus tropicalis'' (extinct) In 2014, following comparison of the mitochondrial cytochrome b DNA sequence of all three species, a new genus, ''Neomonachus'', was erected for the Caribbean and Hawaiian species. The time of divergence between these two, 3.7 million years (Ma) ago, corresponds to the closing of the Central American Seaway by the formation of the Isthmus of Panama. The divergence between Mediterranean seals and the New World clade was dated to 6.3 Ma ago. ==References== 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「Monachus」の詳細全文を読む スポンサード リンク
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