有关标本为标志性的中生代鱼属Sphenodus提供了新的见解
Eduardo Villalobos-Segura1, Manuel Amadori1, Sebastian Stumpf1,2
1Department of Palaeontology, Faculty of Earth Sciences, Geography and Astronomy, University of Vienna, Josef-Holaubek-Platz 2, 1090 Vienna, Austria.
Journal of systematic palaeontology
|July 10, 2025
概括
已灭绝的鱼属Sphenodus,主要是从牙中知道的,是根据骨遗骸重新分类的. 这项研究确立了Archaeogracilidens作为一个新属,解决了化石鱼研究中的分类学不稳定性.
科学领域:
- 古生物学的古生物学
- 系统生物学 系统生物学
- 鱼类学 鱼类学 鱼类学
背景情况:
- 化石鱼和鱼 (Elasmobranchii) 主要是从孤立的牙中知道的,这阻碍了分类学和遗传学研究.
- 已灭绝的中生代鱼属Sphenodus因其基于可变牙特征的分类而带来了分类学挑战.
研究的目的:
- 批判性地审查灭绝的鱼属Sphenodus的系统学和分类学.
- 用骨遗骸重新评估Sphenodus的遗传学和分类学关系.
主要方法:
- 关于Sphenodus和相关类型的详尽文献综述.
- 来自Sphenodus标本的骨特征的比较分析.
- 与Hexanchiformes的现有遗传学假设进行比较.
主要成果:
- 骨分析表明,Sphenodus macer和Sphenodus nitidus是同义词.
- †Sphenodus属被放置在Hexanchiformes中,与Notidanoides密切相关,形成Hexanchidae的兄弟类.
- 用于 †Sphenodus 定义的牙缺乏诊断价值,使该属成为一个有疑义的名字.
结论:
- 对于具有诊断骨材料和保存良好的牙的物种,提出了一个新的属,Archaeogracilidens.
- 这种重新分类为这群化石鱼提供了更稳定的系统框架.
- 这项研究强调了全态标本在解决化石记录中分类学不确定性的重要性.
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