中国科学院南京地质古生物研究所机构知识库

Phosphatized globules with radially arranged pillars were recently recorded from the Lower Cambrian phosphate deposit, Ningqiang, Shaanxi by Yue and Bengtson. These authors interpreted the globules as blastula stage of embryos and the pillars as blastomeres. On the basis of new additional material, we reinterpret these structures as yolk-pyramid stages of possible arthropod eggs. The 20 embryos under present study range from 380 mu m to 600 mu m in diameter and contain about 120 pyramids. Some embryos having a higher number of pyramids are tentatively interpreted as slightly later developmental stages of the same animal. These 543-million-year-old embryos may push back the evolutionary history of the arthropods to a deeper time and also suggest that one important pattern of arthropod development was already present at the beginning of the Cambrian.