首页> 外文期刊>Nature >AMiddle Triassic stem-turtle and the evolution of the turtle body plan
【24h】

AMiddle Triassic stem-turtle and the evolution of the turtle body plan

机译:中三叠纪茎龟与龟体计划的演变

获取原文
获取原文并翻译 | 示例
           

摘要

The origin and early evolution of turtles have long been major contentious issues in vertebrate zoology(1-11). This is due to conflicting character evidence from molecules and morphology and a lack of transitional fossils from the critical time interval. The similar to 220-million-year-old stem-turtle Odontochelys from China(12) has a partly formed shell and many turtle-like features in its post-cranial skeleton. Unlike the 214-million-year-old Proganochelys from Germany and Thailand, it retains marginal teeth and lacks a carapace. Odontochelys is separated by a large temporal gap from the similar to 260-million-year-old Eunotosaurus from South Africa, which has been hypothesized as the earliest stem-turtle(4,5). Here we report a new reptile, Pappochelys, that is structurally and chronologically intermediate between Eunotosaurus and Odontochelys and dates from the Middle Triassic period (similar to 240 million years ago). The three taxa share anteroposteriorly broad trunk ribs that are T-shaped in cross-section and bear sculpturing, elongate dorsal vertebrae, and modified limb girdles. Pappochelys closely resembles Odontochelys in various features of the limb girdles. Unlike Odontochelys, it has a cuirass of robust paired gastralia in place of a plastron. Pappochelys provides new evidence that the plastron partly formed through serial fusion of gastralia(3,13). Its skull has small upper and ventrally open lower temporal fenestrae, supporting the hypothesis of diapsid affinities of turtles(2,7-10,14,15).
机译:长期以来,海龟的起源和早期进化一直是脊椎动物生态学中的主要争议性问题(1-11)。这是由于分子和形态方面的特征证据相互矛盾,以及关键时间间隔内缺乏过渡化石。类似于来自中国的2.2亿年前的海龟Odontochelys(12),其后颅骨骨架具有部分形成的壳和许多类似龟的特征。与来自德国和泰国的2.14亿年前的Proganochelys不同,它保留了牙齿的边缘并且没有甲壳。 Odontochelys与来自南非的2.6亿年前的Eunotosaurus相距较大的时间间隔,后者被认为是最早的茎龟(4,5)。在这里,我们报告了一种新的爬行动物,Pappochelys,在结构和时间上介于中古巨蜥和Odontochelys之间,可追溯到中三叠纪(约2.4亿年前)。这三个分类单元共有前后宽的主干肋骨,这些主干肋骨的横截面为T形,并且具有雕塑感,细长的背椎骨和改良的腰带。腹足类动物在肢体腰带的各种特征上与牙形动物非常相似。与Odontochelys不同,它具有一个结实的配对胃tral,可以代替腹甲。 Pappochelys提供了新的证据,表明plast是部分通过胃serial的连续融合形成的(3,13)。它的头骨上有较小的上颞下腹窗孔,支持了乌龟的亲和性的假设(2,7-10,14,15)。

著录项

  • 来源
    《Nature》 |2015年第7562期|584-587|共4页
  • 作者单位

    Staatliches Museum Nat Kunde Stuttgart, D-70191 Stuttgart, Germany;

    Natl Museum Nat Hist, Dept Paleobiol, Washington, DC 20013 USA;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号