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海洋无脊椎动物的卵及其早期发育阶段的产物在探讨生物分类和系统发育中具有十分重要的作用,然而却常常难以保存为化石或难以辨认,因而未能得到充分的重视.陕南早寒武世宽川铺段(灯影组顶部)发现大量磷酸盐化的球状化石标本,其中的一些保存有十分精细的超微结构,可以辨认出一个卵膜内的受精卵经可能的胚盘形成、囊胚发育、胚盘扩展形成原肠胚直至胚胎的组织分化和幼体孵化的较为完整的演化序列.这一发现及进一步研究将为早寒武世早期后生动物起源、分类、辐射演化及个体发育提供不可多得的实证材料.
The eggs of marine invertebrates and their early developmental stages are of great importance in the taxonomy and phylogeny of development, yet are often difficult to preserve as fossils or illegible, thus failing to receive sufficient attention. A large number of phosphated spherical fossil specimens were found at the Kuanchuanpu Section of the Wu Shi (the top of the Dengying group), some of which preserved a very fine ultrastructure in which a fertilized ovum within the egg membrane was identified as being likely to form a blastula Development and blastocyst expansion to form a more complete evolutionary sequence of gastrula embryos until embryonic tissue differentiation and larvae hatch.This discovery and further study will provide evidence for the origin, classification, evolution of radiation and individual development of metazoan early metazoans More empirical material.