[1] Chinese Acad Sci, Nanjing Inst Geol & Palaeontol, State Key Lab Palaeobiol & Stratig, Nanjing 210008, Peoples R China
[2] Chinese Acad Sci, Ctr Excellence Life & Paleoenvironm, Nanjing 210008, Peoples R China
[3] Chicago Bot Garden, Glencoe, IL 60022 USA
[4] Univ Chinese Acad Sci, Beijing 100049, Peoples R China