1. Yunnan Academy of Biodiversity; Southwest Forestry University; Kunming 650224 China
2. Department of Botany; National Museum of Natural History; MRC-166, Smithsonian Institution Washington DC 20013-7012 USA
3. Key Laboratory for Plant Diversity and Biogeography of East Asia; Kunming Institute of Botany; Chinese Academy of Sciences; Kunming 650204 China