New advances in the study of the Sinian Doushantuoan acritarch genus Tianzhushania

The genus of large-sized acanthomorphic acritarchs ,Tianzhushania,was named from Tianzhu Mountain in Changyang County,Hubei Province,where it was first described,and its typical species was first found from chert nodules(in thin sections )from the Sinian Doushantuo Formation.In this paper,the authors summarize the reports and researches about the genus published at home and abroad in the past20-odd years.On that basis,combined with the latest study of the relationships between Tianzhushania tuberifera Yin,Gao and Xing2000,preserved in siliceous rocks,and Megasphaera ornata Xiao and Knoll2000,which are pellet body fossils preserved by prophorization in the Sinian Doushantuo Formation,the authors discuss such problems as the morphological features,geographical distribution,stratigraphic signifi-cance and possible affinity of the large-sized acanthomorphic genus Tianzhushania.