陕西宁强埃迪卡拉系顶部管状化石Sinotubulites形态学与古生态学新知

陕西宁强选将坪地区埃迪卡拉系灯影组高家山段上部的碎屑白云岩中产出大量磷酸盐化三维立体保存的Sinotubulites化石,这为埃迪卡拉纪末期生物的演化及多样性研究提供了一个很好的窗口。文中通过对Si-notubulites的形态结构、纹饰特征、保存特征等方面的观察研究,认为Sinotubulites管体外壁上不规则的褶皱状纹饰是变形过程中展现出的各种形态,而不是管体固有的纹饰形态特征。并且根据管体内外层管壁的不同形态学特征以及在原始生态条件下弯曲生长的管体,将Sinotubulites解释为表栖平躺生物。Sinotubulites可能具有一定的蠕动能力,而不规则褶皱状外壁在变形过程中可以产生微弱的蠕动力,使得管体对自身的位置得以调整。

MORPHOLOGY AND PALAEOECOLOGY OF THE LATE EDIACARAN TUBULAR FOSSIL SINOTUBULITES

The Gaojiashan Member of the upper Ediacaran Dengying Formation in southern Shaanxi has yielded a diversity of abundant three-dimensionally phosphatized tubular fossils and problematics.Sinotubulites is a mm-to cm-scale tubular fossil having characteristic tube-within-tube construction.On the basis of the transverse ridges of the exterior(outermost) wall,we suggest that their irregular fold-shaped morphology is resulted from deformation.Integrating the various observed morphologies of the tube walls and their ridge form,together with the occurrence of strongly curved tubes,we further suggest that Sinotubulites were epibenthic organisms lying recumbently on the substrate and we argue that they may have had weak peristaltic motility probably allied to adjustments of the tube as indicated by the irregular fold-shaped construction of their exterior tube wall.