贵州省瓮安县上震旦统陡山沱组生物化石群的发现

Discovery of Fossils in the Upper Sinian System Doushantuo Formation Phosphate Rocks in Weng' an County,Guizhou Province

在贵州省瓮安县上震旦统陡山沱组磷块岩（距今５８０ Ｍａ）中，发现有大量的多细胞藻类、海绵和动物胚胎化石。多细胞藻类以真红藻为主。海绵为单轴类，完整个体大小７５０～１ ５５０ μｍ ；它们的软组织细节及许多特征构造包括表层细胞、孔壁胞、变形细胞、骨针细胞和海绵腔等都可见到。动物胚胎多为球形，直径５００ μｍ 左右。它们有些是海绵幼虫和两囊幼虫。这一化石群的发现，至少将动物大量出现的时间向前推进了３０ Ｍａ，并使“寒武纪生命大爆炸”理论面临挑战。

Plenty of multicellular alage, sponge and embryos have been discovered in the upper Sinian system Doushantuo Formation phosphate rocks(580 million years) in Weng’an county, Guizhou Province. These aglae are the red algal class. The sponge are monaxonid Demospongiae. Size of individual sponge is only 750～1 500 μm. Preserved sponge soft tissues includ the epidermis, porocytes, amoebocytes, sclerocytes and spongocoel. Animals embryos are most of glubular, measuring about 500 μm in diameter. A part of them are parenchymella larva and amphiblastula larva. Discovered the fauna, the time of origins animals will be dated back about 30 million years at least more than former times and the theory that “Animals were Suddenly Explosion in Cambrian” will be challenged.