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The domed Rodrigues giant tortoise (''Cylindraspis peltastes'') was a species of giant tortoises in the Testudinidae family. It was endemic to Rodrigues. It appears to have become extinct around 1800.〔 The domed Rodrigues tortoise was one of the smallest of the giant tortoises of the Indian Ocean, reaching a length of just over 40 cm and an estimated weight of around 12 kg. A low grazer of grasses, it shared Rodrigues Island with its much larger relative, the saddle-backed Rodrigues giant tortoise, which browsed the taller vegetation. Both species were descended from an ancestral species on Mauritius (an ancestor of ''Cylindraspis inepta''), which colonised Rodrigues by sea many millions of years ago, and then differentiated into the two Rodrigues species. At the time of the arrival of human settlers, dense tortoise herds of many thousands were reported on Rodrigues. Like many island species, they were reported to have been friendly and unafraid of humans. However, in the ensuing years, massive harvesting for food and the introduction of invasive alien species rapidly exterminated the tortoises. A surviving tortoise was reported on Rodrigues in 1795, at the bottom of a ravine. As late as 1802, there is mention of survivors reportedly being killed in the large fires used to clear the island's vegetation for agriculture.〔(【引用サイトリンク】title=Cylindraspis peltastes ) Retrieved on 15 May 2015.〕〔Cheke, A., Hume, J.: ''Lost Land of the Dodo, An Ecological History of Mauritius, Réunion & Rordrigues''. T & AD Poyser, London.2008.〕 It has subsequently been discovered that the browsing herds of tortoises filled an essential role in the island's ecosystem and the regeneration of its forests. In recognition of this fact, measures have been undertaken to introduce replacements, in the form of similar species of tortoises from other parts of the world, to assist in the rebuilding of Rodrigues' devastated environment. The replacement species for the domed Rodrigues tortoise was chosen to be the radiated tortoise (''Astrochelys radiata'') of Madagascar, which is similar in size and habit.〔Cheke, A., Hume, J.: ''Lost Land of the Dodo, An Ecological History of Mauritius, Réunion & Rordrigues''. T & AD Poyser, London.2008.〕 ==See also== ; 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「Domed Rodrigues giant tortoise」の詳細全文を読む スポンサード リンク
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