陕西宁强早寒武世磷酸盐化具星状表饰胚胎化石研究

后生动物胚胎化石研究对了解寒武纪大爆发中生命的个体及系统发育具有十分重要的意义。陕南早寒武世灯影组宽川铺段发现大量磷酸盐化的球状化石标本,其中的一些为保存有十分精细的星状表饰的胚胎化石,目前发现至少3种具星状纹饰的胚胎化石:圆球状胚胎、具中央收缩带的球状胚胎和表面具“拉伸构造”的花生状胚胎,其中后者为新类型。研究表明,此新类型在演化序列上处于圆球状胚胎、具中央收缩带的球状胚胎发育阶段之后,是胚胎向成体演化的一个重要中间过渡环节,这一发现为研究早寒武世早期后生动物胚胎及个体发育提供了新线索。

STUDIES ON PHOSPHATIZED EMBRYOS WITH STAR-LIKE TEXTURE FROM THE EARLY CAMBRIAN IN NINGQIANG, SOUTH SHAANXI, CHINA

Animal embryos are of great significance in the study of individual and systematic development. A large amount of phosphatized globular fossils were retrieved from the early Cambrian Kuangchuanpu Member of the Dengying Formation, south Shaanxi, some of which are preserved with elaborate star-like texture. A preliminary study indicates that at least 3 types of embryos with star-like texture can be distinguished from globular fossils. They include globular embryos, globular embryos with central girdle belt and peanut-like embryo with tensile structure, the peanut-like embryo is a new type. It is shown that the new type appears after the globular embryos and globular embryos with central girdle belt during the embryo-development. It is interpreted as a key transition from the embryo to the adult. These discoveries of embryos provide new clue for embryogenesis and individual development in the Early Cambrian.