1 State Key Laboratory of Palaeobiology and Stratigraphy; Nanjing Institute of Geology and Palaeontology; Chinese Academy of Sciences; Nanjing 210008; China. dyhuang@nigpas.ac.cn.
2 State Key Laboratory of Palaeobiology and Stratigraphy; Nanjing Institute of Geology and Palaeontology; Chinese Academy of Sciences; Nanjing 210008; China. cycai@nigpas.ac.cn.
3 Manaaki Whenua - Landcare Research; Private Bag 92170; Auckland; New Zealand; School of Biological Sciences; The University of Auckland; Auckland; New Zealand. zhangZ@landcareresearch.co.nz.