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| synonyms = ''Neopropithecus'' Lamberton, 1936 | synonyms_ref = | range_map = Mesopropithecus range map.svg | range_map_caption = Subfossil sites for ''Mesopropithecus'' = ''M. dolichobrachion''; = ''M. globiceps''; = ''M. pithecoides'' | range_map_alt = Map of Madagascar, off the southeast coast of Africa, with one red dot in the extreme north of the island, two blue dots near the middle, and seven green dots in the southwest and west parts of the island. }} ''Mesopropithecus'' is an extinct genus of small to medium-sized lemur, or strepsirrhine primate, from Madagascar that includes three species, ''M. dolichobrachion'', ''M. globiceps'', and ''M. pithecoides''. Together with ''Palaeopropithecus'', ''Archaeoindris'', and ''Babakotia'', it is part of the sloth lemur family (Palaeopropithecidae). Once thought to be an indriid because its skull is similar to that of living sifakas, a recently discovered postcranial skeleton shows ''Mesopropithecus'' had longer forelimbs than hindlimbs—a distinctive trait shared by sloth lemurs but not by indriids. However, as it had the shortest forelimbs of all sloth lemurs, it is thought that ''Mesopropithecus'' was more quadrupedal and did not use suspension as much as the other sloth lemurs. All three species ate leaves, fruits, and seeds, but the proportions were different. ''M. pithecoides'' was primarily a leaf-eater (folivores), but also ate fruit and occasionally seeds. ''M. globiceps'' ate a mix of fruits and leaves, as well as a larger quantity of seeds than ''M. pithecoides''. ''M. dolichobrachion'' also consumed a mixed diet of fruits and leaves, but analysis of its teeth suggests that it was more of a seed predator than the other two species. Although rare, the three species were widely distributed across the island yet allopatric to each other, with ''M. dolichobrachion'' in the north, ''M. pithecoides'' in the south and west, and ''M. globiceps'' in the center of the island. ''M. dolichobrachion'' was the most distinct of the three species due to its longer arms. ''Mesopropithecus'' was one of the smallest of the extinct subfossil lemurs, but was still slightly larger than the largest living lemurs. Known only from subfossil remains, it died out after the arrival of humans on the island, probably due to hunting pressure and habitat destruction. ==Classification and phylogeny== ''Mesopropithecus'' is a genus within the sloth lemur family (Palaeopropithecidae), which includes three other genera: ''Palaeopropithecus'', ''Archaeoindris'', and ''Babakotia''. This family in turn belongs to the infraorder Lemuriformes, which includes all the Malagasy lemurs. ''Mesopropithecus'' was named in 1905 by Herbert F. Standing using four skulls found at Ampasambazimba. He noted that the animal had characteristics of both ''Palaeopropithecus'' and the living sifakas (''Propithecus''). In 1936, Charles Lamberton defined ''Neopropithecus globiceps'' (based on one skull from Tsirave) and ''N. platyfrons'' (based on two skulls from Anavoha). He thought that ''Neopropithecus'' was a separate, intermediate genus between ''Mesopropithecus'' and ''Propithecus''. In 1971, paleoanthropologist Ian Tattersall merged ''N. platyfrons'' into ''N. globiceps'' and ''Neopropithecus'' into ''Mesopropithecus''. Until 1986, ''Mesopropithecus'' was only known from cranial (skull) remains from central and southern Madagascar, and because these are similar to teeth and skulls of living indriids, particularly those of Verreaux's Sifaka (''Propithecus verreauxi''), ''Mesopropithecus'' was often assigned to the family Indriidae. For example, in 1974, Tattersall and Schwartz labeled ''Mesopropithecus'' as a sister group to sifakas. With the discovery of an associated skeleton of ''M. dolichobrachion'' near Ankarana in 1986, it became clear that ''Mesopropithecus'' shared distinct traits with sloth lemurs. Unlike the indriids, but like the sloth lemurs, they had elongated forelimbs and other adaptations for arboreal suspension (hanging in trees), linking them most closely to family Paleaeopropithecidae. A comparison of these morphological traits between the sloth lemurs and indriids suggest that ''Mesopropithecus'' was the first genus to diverge within the sloth lemur family. 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「Mesopropithecus」の詳細全文を読む スポンサード リンク
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