Abstract The fossil history of Neogene chelonioid sea turtles from South America is very incomplete. To date, only the isolated remains of dermochelyids and stem-cheloniids have been reported from the Miocene Pacific coast, and a single indeterminate dermochelyid is known from the early Miocene of Patagonia. Here, we describe a partial lower jaw of a fossil chelonioid from the late Miocene of Paraná city, in the Entre Ríos Province of Argentina. This new specimen displays a character state combination consistent with attribution to stem-Cheloniidae, and thus represents the first record of a late Miocene chelonioid from the southwestern Atlantic margin of South America. Agustín Falbo [agustinf_25@hotmail.com], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo 470 (C1405DJR), Buenos Aires, Argentina; Federico Agnolin [fedeagnolin@yahoo.com.ar], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Av. Ángel Gallardo 470 (C1405DJR), Buenos Aires, Argentina. Fundación de Historia Natural ‘Félix de Azara’, Universidad Maimónides, Hidalgo 775 (C1405BDB), Buenos Aires, Argentina.

中文翻译：

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阿根廷中新世晚期的龟类海龟（Testudines，Pan-Cheloniidae）的首次记录

摘要 南美洲新近纪类龟类海龟的化石历史非常不完整。迄今为止，在中新世太平洋沿岸仅报道了皮甲类动物和茎龟类的分离遗骸，并且在巴塔哥尼亚的中新世早期发现了一个不确定的皮甲类动物。在这里，我们描述了来自阿根廷恩特雷里奥斯省巴拉那市晚中新世的海龟化石的部分下颌。这个新标本显示出与茎海龟科的属性一致的特征状态组合，因此代表了来自南美洲西南大西洋边缘的晚中新世海龟类的第一个记录。Agustín Falbo [agustinf_25@hotmail.com], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales 'Bernardino Rivadavia', Av. Ángel Gallardo 470 (C1405DJR)，阿根廷布宜诺斯艾利斯；Federico Agnolin [fedeagnolin@yahoo.com.ar], Laboratorio de Anatomía Comparada y Evolución de los Vertebrados, Museo Argentino de Ciencias Naturales 'Bernardino Rivadavia', Av. Ángel Gallardo 470 (C1405DJR)，阿根廷布宜诺斯艾利斯。Fundación de Historia Natural 'Félix de Azara', Universidad Maimónides, Hidalgo 775 (C1405BDB), Buenos Aires, Argentina。