概括
在阿根廷发现的化石海显著将南美海化石记录推迟了6000万年. 这些特里亚斯纪时代的化石代表了一个新的基底海属和物种,Palaeochersis talampayensis.
科学领域:
- 古生物学的古生物学
- 脊椎动物古生物学 脊椎动物古生物学
- 中生代爬行动物 中生代爬行动物
背景情况:
- 早期乌的化石记录稀少,特别是在南半球.
- 乌 (Testudines) 的进化历史和多样化仍然是活跃研究的领域.
- 以前在南美洲发现的海并没有延伸到三叠纪时期.
研究的目的:
- 为了描述来自阿根廷三叠纪的新基底海化石.
- 重新评估早期海的进化关系和多样化.
- 扩大已知的时间和地理范围的海在南美洲.
主要方法:
- 从阿根廷西北部的诺里亚 (特里亚斯纪晚期) 层挖掘和准备两个化石乌骨.
- 化石材料的比较解剖学分析,专注于乌的关键骨特征.
- 遗传学分析以确定Testudines.内新分类的进化关系.
主要成果:
- 发现了两个新的化石乌骨,包括一个几乎完整的标本,代表一个新的属和物种:Palaeochersis talampayensis.
- 帕莱奥切尔西斯 (Palaeochersis talampayensis) 属于澳大利亚类 (Australochelidae) 科,以前只从南非的罗纪早期 (Early Jurassic) 知道.
- 这一新发现将南美海化石记录延伸到三叠纪晚期,比以前知道的时间早大约6000万年.
结论:
- Australochelidae代表了海的基底血统,Palaeochersis talampayensis为它们的形态和分布提供了关键的见解.
- 乌的多样性已经存在于三纪晚期,挑战了他们进化时间线的先前概念.
- 这些发现表明,包括Casichelydia在内的主要乌类,可能起源于罗纪时期.
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