Archosauriform endocranial morphology and osteological evidence for semiaquatic sensory adaptations in phytosaurs
Archosauriform endocranial morphology and osteological evidence for semiaquatic sensory adaptations in phytosaurs
复制标题
植龙类半水生感觉适应的主龙颅内形态和骨学证据
作者：
Emily J Lessner;M. Stocker
对初龙形类的颅内资料的研究，在体型、神经通路和感觉能力的演化上取得了进展。然而，大部分研究都集中在鸟线主龙类上，导致对主龙类的偏见。植龙类，一个假设的姐妹分类群或早期分支的成员初龙类，提供了一个潜在的外群条件。大多数以前的植龙类颅内研究都没有使用现代技术，并且集中在植龙类的衍生成员上。我们提出了一个比较CT检查的内部颅骨解剖的Wannia scurriensis，最基本的已知parasuchid植龙。Wannia scurriensis与现存的鳄鱼类和衍生的植龙类在一般的颅内形状、大的垂体窝和三叉神经（CN V）神经支配方面表现出一些总体相似性，但作为一个整体，内管与鳄鱼类和其他植龙类有明显的差异。松果体区域像其他植龙一样向背侧扩张，但也向侧面扩张（以前未被认识）。CN V比Parasuchus hislopi，Machaeroprosopus mccauleyi或Smilosuchus gregorii更背侧位置离开脑桥。Wannia scurriensis也表现出一个更大的垂体窝相对于脑的大小比观察到的P. hislopi或S。格雷戈里，这可能表明更快的增长。保存完好的半规管具有侧管，其角度比派生的植龙更前倾。从大CN V广泛的面部神经支配表明增加喙敏感性和mechanoreceptive能力，在短吻鳄密西西比。植龙类和短吻鳄类之间的这些颅内相似性表明水生生活方式的生态和功能结果是保守的，并强调需要进一步探索初龙形目之间的颅内解剖。
The examination of endocranial data of archosauriforms has led to advances on the evolution of body size, nerve pathways, and sensory abilities. However, much of that research has focused on bird‐line archosaurs, resulting in a skewed view of Archosauria. Phytosauria, a hypothesized sister taxon to or early‐branching member of Archosauria, provides a potential outgroup condition. Most previous phytosaur endocranial studies were executed without the use of modern technology and focused on derived members of Phytosauria. We present a comparative CT examination of the internal cranial anatomy of Wannia scurriensis, the most basal known parasuchid phytosaur. Wannia scurriensis shows some overall similarity with extant crocodylians and derived phytosaurs in general endocranial shape, a large hypophyseal fossa, and trigeminal (CN V) innervation, but as a whole, the endocast has noticeable differences to crocodylians and other phytosaurs. The pineal region is expanded dorsally as in other phytosaurs but also laterally (previously unrecognized). CN V exits the pons in a more dorsal position than in Parasuchus hislopi, Machaeroprosopus mccauleyi, or Smilosuchus gregorii. Wannia scurriensis also exhibits a larger hypophyseal fossa relative to brain size than observed in P. hislopi or S. gregorii, which may indicate more rapid growth. The well‐preserved semicircular canals have lateral canals that are angled more anteroventrally than in derived phytosaurs. Extensive facial innervation from the large CN V indicates increased rostrum sensitivity and mechanoreceptive abilities as in Alligator mississippiensis. These endocranial similarities among phytosaurs and with Alligator indicate conserved ecological and functional results of an aquatic lifestyle, and highlight a need for further exploration of endocranial anatomy among Archosauriformes.
DOI：
10.1111/j.1469-185x.2010.00137.x
发表时间：
2011-02
影响因子：
--
作者：
Sander PM;Christian A;Clauss M;Fechner R;Gee CT;Griebeler EM;Gunga HC;Hummel J;Mallison H;Perry SF;Preuschoft H;Rauhut OW;Remes K;Tütken T;Wings O;Witzel U
通讯作者：
Witzel U