一个巨大的干群 chaetognathath
Tae-Yoon S Park1,2, Morten Lunde Nielsen1,3,4, Luke A Parry5
1Division of Earth Sciences, Korea Polar Research Institute, 26 Songdomirae-ro Yeonsu-gu, Incheon 21990, Republic of Korea.
Science advances
|January 3, 2024
概括
一个新的化石, *Timorebestia koprii*,来自坎布里亚时代的Sirius Passet Lagerstätte,揭示了早期的chaetognaths是大型海底捕食者. 它的独特特征证实了它在chaetognath茎上的位置,这表明它在古代海洋生态系统中发挥了更高的食量作用.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 海洋生物学 海洋生物学
背景情况:
- 柴托格纳斯,或箭虫,是古老的海底捕食者,可以追溯到坎布里亚时期.
- 之前对像*Amiskwia sagittiformis*这样的相关化石的解释对于它们的遗传学位置不确定.
- 了解早期的chaetognath进化是重建古代海洋食物网的关键.
研究的目的:
- 为了描述一个新的大型茎状虫化石,来自低坎布里亚时代的*Timorebestia koprii*,来自Sirius Passet Lagerstätte.
- 为了确定 *T. koprii* 在 chaetognath 血统中的遗传位置.
- 为了推断早期Chaetognaths在坎布里亚海洋生态系统中的生态作用.
主要方法:
- 关于 *Timorebestia koprii* 的化石描述和形态分析.
- 与已知chaetognaths和相关种类的比较解剖学.
- 基因分析基于共同的解剖特征,特别是腹腔腺.
主要成果:
- *Timorebestia koprii*被描述的特征包括侧翼和尾翼,天线和一个部装置.
- 一个共同的腹腔结节的存在坚定地将T. koprii*置于chaetognath干系中.
- 大尺寸和肠道含量表明早期的chaetognaths是重要的捕食者.
结论:
- *Timorebestia koprii*代表了一个大型的,早期的chaetognath,扩大了我们对它们祖先形态学的理解.
- 这一发现巩固了在chaetognath干群中某些坎布里亚化石的遗传学位置.
- 早期的chaetognaths可能在坎布里亚海生态系统中占据了比它们的现代同行更主导的掠夺性角色.
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