在一个特里亚斯纪晚期的古龙 (Aetosauria: Typothorax coccinarum) 中,不一致的本体遗传成熟度指标
William G Parker1, William A Reyes1,2, Adam D Marsh1
1Department of Science and Resource Management, Petrified Forest National Park, Petrified Forest, USA.
Anatomical record (Hoboken, N.J. : 2007)
|November 8, 2023
概括
一个巨大的新化石的Typothorax coccinarum,一种类型的 pseudosuchian archosaur,揭示了大体大小是可能在这个群体. 这种标本挑战了关于aetosaurs骨成熟度和成长的假设.
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:
- 伪木类类动物的最大体型尚不清楚.
- 亚类动物 (Aetosauria) 是一种伪类动物群,其体型有显著的变化.
- 之前的aetosaur标本的长度从1米到5米不等.
研究的目的:
- 描述一个新的,异常大的标本的aetosaurTypothorax coccinarum.
- 调查aetosaurs体型,骨成熟度和生长指标之间的关系.
- 为了确定非desmatosuchin aetosaurs是否可以达到较大的身体尺寸.
主要方法:
- 从石化森林国家公园挖掘和分析一个大型甲龙标本 (PEFO 42506).
- 作为骨成熟度指标,检查脊椎神经中心部同骨化.
- 对骨干肋骨的骨质组织学分析,以评估生长线和外部基本系统的存在.
主要成果:
- 新的Typothorax coccinarum标本是迄今为止发现的最大的aetosaur,几乎是其他已知的标本的两倍.
- 该标本表现出未融合的神经中心,这表明它没有骨成熟,与较小的标本相反.
- 骨组织学显示了许多生长线,但没有外部基本系统,进一步表明尽管体积大,但不成熟.
结论:
- 神经中心线共骨化可能不是aetosaurs中ontogenetic阶段的可靠指标.
- 骨成熟度和身体大小可能在aetosaurs中不一致.
- 这一发现表明非desmatosuchin aetosaurs可以达到大尺寸,并表明一些可能有无限期的增长.
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