1. State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences Beijing 100093 China
2. University of Chinese Academy of Sciences Beijing 100049 China
3. Missouri Botanical Garden, 4344 Shaw Blvd. St. Louis Missouri 63110 U.S.A.
4. Institut Systématique, Evolution, Biodiversité (ISYEB), Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, Université des Antilles, EPHE, 57 rue Cuvier, CP39 Paris 75005 France