在南美洲的第一个Baryonychinae (Theropoda,Spinosauridae) 牙上
Mauro B S Lacerda1, Paulo R L Aragão2, Fabiana S Vieira3
1Pós-Graduação em Zoologia; Instituto de Ciências Biológicas; Universidade Federal de Minas Gerais; Belo Horizonte; Minas Gerais 31270-901; Brazil.. mbslacerda@ufmg.br.
Zootaxa
|July 30, 2023
概括
南美首次发现Baryonychinae旋类化石,特别是来自巴西的三个低白纪牙冠,揭示了与这种恐龙类结合它们的关键特征. 这些古老的旋类动物发现扩大了它们已知的范围,并为早期进化提供了洞察力.
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
- 中生时期的热类动物 (theropoda)
背景情况:
- 脊类 (Spinosauridae) 是一种多样化的恐龙类,已知来自冈多瓦纳和劳拉西亚大陆.
- 细菌家族Baryonychinae,以特殊的牙特征为特征,在南美洲的化石记录有限.
- 了解螺旋类的分布和进化需要识别不同古地理区域的化石证据.
研究的目的:
- 报告南美洲首次出现Baryonychinae旋类动物标本.
- 分析新发现的螺旋osaurid 牙冠的遗传学和形态学亲缘关系.
- 为了研究这些早期的旋类动物记录的古生物地理和进化含义.
主要方法:
- 来自巴西的三个低白时期的螺旋类动物牙冠的形态分析.
- 使用基于牙和基于冠状的类动物的数据集进行了家族遗传学分析.
- 多变量统计分析 (区分和集群分析) 用于形态比较.
主要成果:
- 来自巴西的三个低白时期的螺旋osaurid 牙冠表现出 baryonychine 特性,包括状形态,静脉面膜和带有微小牙的状牙.
- 遗传学分析证实,这些标本属于螺旋osaurid 类,可能与其他 baryonychines 和一些螺旋osaurines 形成一个多体.
- 形态测量分析表明与Suchomimus和baryonychines有相似之处,扩大了这个类的已知的古生物学地理范围到西贡德瓦纳.
结论:
- 这些发现代表了全球最古老的螺旋类记录,也是南美洲Baryonychinae的第一个,对螺旋类出现和进化的假设产生了重大影响.
- 在低白时期的菲利兹沙漠形成中存在多种螺旋类类的存在表明了复杂的古生物学环境.
- 这一发现凸显了南美化石遗址对于了解白时期恐龙多样性和生物地理的重要性.
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