宽川铺生物群中球状胚胎化石表面刺状结构研究

Fossil eggs and embryos from the Lower Cambrian Kuanchuanpu Member of the Dengying Formation at Ningqiang in southern China provide a unique window for investigating the ontogeny of metazoans. However, these eggs and embryos are very different in size and most of them lack comparable structures with adult, which make it hard to determine affinity of them. Embryos are preserved in 3D as phosphatized permineralizations with superficial structures, and interior anatomy revealed in partly decayed embryos. Different species share a similar naked egg membrane and stellate cuticle which indicate that: 1)It is improper to judge affinity by size or superficial structure of embryos; 2)It is postulated that the stellate cuticle would provide physical protection and dispersal to suitable habitat. Such properties were also observed in extant sea anemone embryos; 3)The stellate Olivooides may represent the primitive larva, which could be the evidence of indirect development. Therefore, to trace the origin of the direct and indirect development patterns, people should find the answer in much older strata.