中国地质科学院基本科研业务费资助项目编号YWF201608;中国科学院南京地质与古生物研究所资助项目编号421060105的成果。AcknowledgementsThis work was financially supported by the Fundamental Research Funds of Chinese Academy of Geological SciencesYWF201608;the project of Nanjing Institute of Geology and Paleontology,Chinese Academy of SciencesNo.Y421060105.