ANATOMY OF THECODONT REPTILE EUPARKERIA CAPENSIS BROOM
ANATOMY OF THECODONT REPTILE EUPARKERIA CAPENSIS BROOM
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DOI：
10.1098/rstb.1965.0003
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发表时间：
1965-01-01
影响因子：
6.3
通讯作者：
EWER, RF
中科院分区：
文献类型：
--
作者：
EWER, RF
南非博物馆的Euparkeria标本最初由Broom（1913年）描述，后来由Haughton（1922年）研究，现已使用牙槌进一步制备。此外，还准备和研究了D. M. s .沃森教授收集的材料。在Aliwal North进行的调查表明，所有的材料可能代表一个单一的发现，而靠近城镇的一小块Cynognathus带页岩被认为是最有可能的地点。在上述标本的基础上，给出了大部分骨骼的详细描述，唯一未知或不完全了解的部分是腕骨和掌骨，脑壳和尾椎。从功能角度讨论以下特征：颅骨结构；四肢和腰带；脊柱和肋骨。头骨虽然显示出对掠食性习惯的一些适应，但相对来说并不专门化，因此随后向杂食甚至素食的趋势逆转也不是不可能的。对下颌肌肉可能排列的考虑表明，祖龙的眶前孔最初并不是与翼状突D肌的发育有关。对四肢及其腰带的研究表明，Euparkeria是兼性两足动物，当采用这种步态时，股骨被置于垂直位置，尽管它们在休息或缓慢移动时一定是水平保持的。提示肋骨关节沿脊柱长度位置的改变与肺通气的效率有关。神经棘尖端的扩张被证明与真皮盔甲的发育无关，而是与棘横肌系统肌肉的排列有关。因此，用于指定这些扩展的术语“鳞片桌”被放弃，它们被简单地称为脊柱桌。本文还简要讨论了真派克亚与其他类群的关系。Euparkeria显示了一些与高度食肉习惯和运动效率增加相关的渐进特征，并保留了一些原始特征。以前的作者倾向于强调这些类型特征中的一种或另一种，并相应地将真斑虫分类为高级形式或非常原始的形式：由此提出的系统位置的变化范围从包括在蝶科（v. Huene 1962）到红斑虫科（Hughes 1963）。结论是，真帕克氏菌虽然是一种进进形式，但与后一科密切相关，因此暂时将其分类可能是方便的。它很可能是先进的伪类动物的直接祖先，比如鸟龙类和长尾龙类，也可能是原蜥脚类和蜥脚类动物的直接祖先，但不是鸟臀目动物或鸟类的直接祖先，而且它的进化程度略高，不可能是直龙科的直接祖先，然而，它与直龙科有着密切的关系。
The SouthAfrican Museum specimens of Euparkeria originally described by Broom (1913) and later studied by Haughton (1922) have been further prepared using the dental mallet. In addition, material in Professor D. M. S. Watson''s collection has been prepared and studied. As a result of inquiries made at Aliwal North, it is suggested that all the material may represent a single find and a small exposure of Cynognathus zone shale close to the town is considered to be the most probable location of the site. On the basis of the specimens already mentioned a detailed description of most of the skeleton is given, the only parts remaining unknown, or incompletely known, being the carpus and manus, the braincase and the caudal vertebrae. The following features are discussed in functional terms: skull architecture; the limbs and their girdles; the vertebral column and ribs. The skull, although showing some adaptation to predacious habits, is relatively unspecialzed and a subsequent reversal of trend towards a more omnivorous or even vegetarian diet is not impossible. A consideration of the probable arrangement of the jaw muscles suggests that the antorbital fenestra of the archosaurs was not originally evolved in relation to the development of the pterygoideus D musculature. A study of the limbs and their girdles indicates that Euparkeria was facultatively bipedal and that when this gait was adopted the femora were brought into a vertical position, although they must have been held horizontally while at rest or moving slowly. It is suggested that the alteration in position of the rib articulations along the length of the vertebral column is related to efficiency of pulmonary ventilation. Expansion of the tips of the neural spines is shown to be related not to the development of dermal armour but to the arrangement of the muscles of the transversospinalis system. The term "scute tables" used to designate these expansions is therefore abandoned and they are referred to simply as spine tables. The relationships of Euparkeria to other groups is briefly discussed. Euparkeria shows a number of progressive features related to a highly carnivorous habit and increased locomotor efficiency combined with retention of several primitive characters. Previous authors have tended to lay emphasis on one or other of these types of characteristic and accordingly classify Euparkeria either as an advanced form or as a very primitive one: the consequent variation in proposed systematic position ranges from inclusion in the Sphenosuchidae (v. Huene 1962) to the Erythrosuchidae (Hughes 1963). It is concluded that Euparkeria, although a progressive form, is closely related to the latter family with which it may be convenient, for the time being, to classify it. It could well have been directly ancestral to advanced pseudosuchians such as Ornithosuchus and Hesperosuchus and possibly to the prosauro-pods and sauropods but not to the ornithischians or the birds and was a trifle too advanced to have been directly ancestral to the Aetosauridae, to which it is, however, closely related.