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The genus ''Bassaricyon'' consists of small Neotropical procyonids, popularly known as olingos . They are native to the rainforests of Central and South America from Nicaragua to Peru. They are arboreal and nocturnal, and live at elevations from sea level to 2,750 m. Olingos closely resemble the kinkajou in morphology and habits, though they lack prehensile tails and extrudable tongues, have more extended muzzles, and possess anal scent glands. Genetic studies have shown that the closest relatives of the olingos are actually the coatis;〔 the divergence between the two groups is estimated to have occurred about 10.2 million years (Ma) ago,〔 while kinkajous split off from the other extant procyonids about 22.6 Ma ago. The similarities between kinkajous and olingos are thus an example of parallel evolution. == Species == There is disagreement on the number of species in this genus, with some taxonomists splitting the populations into as many as five species (adding ''B. pauli'' to the list below), two species (dropping ''B. medius'' and ''B. neblina''), or just a single species (''B. gabbi'').〔Reid, F. & K. Helgen (2008). (Bassaricyon gabbii ). In: IUCN 2013. ''IUCN Red List of Threatened Species'. Version 2013.1. Downloaded on 16 August 2013.〕 Until recently, only the northern olingo (''B. gabbii'') was particularly well-known, and it was usually confusingly referred to simply as an olingo. Olingos are quite rare in zoos and are often misidentified as kinkajous. An undescribed olingo, similar to but distinct from ''B. alleni'', was discovered in 2006 by Kristofer Helgen at Las Maquinas in the Andes of Ecuador.〔Handbook of the Mammals of the World (2009). ISBN 978-84-96553-49-1〕 He named this species ''B. neblina'' or olinguito and presented his findings on August 15, 2013. With data derived from anatomy, morphometrics, nuclear and mitochondrial DNA, field observations, and geographic range modeling, Helgen and coworkers demonstrated that four olingo species can be recognized:〔 * ''Bassaricyon alleni'', lowlands of Guyana, Venezuela, and in Colombia, Ecuador, Peru and Bolivia east of the Andes; * ''Bassaricyon gabbii'', Central American, lowlands and highlands of Nicaragua, Costa Rica, and western Panama; * ''Bassaricyon medius'', lowlands of Panama and in Colombia and Ecuador west of the Andes; and * ''Bassaricyon neblina'', a montane species endemic to cloud forests in the Andes of Colombia and Ecuador.〔 The diversification of the genus apparently started about 3.5 million years ago, when ''B. neblina'' branched off from the others; ''B. gabbii'' then split off about 1.8 Ma ago, and the two lowland species, ''B. alleni'' and ''B. medius'', diverged about 1.3 Ma ago.〔 The dating and biogeography modeling suggest that the earliest diversification of the genus took place in northwestern South America shortly after the ancestors of olingos first invaded the continent from Central America as part of the Great American Interchange.〔 |2=''B. neblina'' (olinguito) }}}} 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「Bassaricyon」の詳細全文を読む スポンサード リンク
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