1. Department of Botany; MRC-166; Smithsonian Institution PO Box 37012, Washington DC 20013-7012 USA
2. Key Laboratory of Plant Resources Conservation and Utilization; College of Biology and Environmental Sciences; Jishou University; Jishou 416000 Hunan China
3. Key Laboratory for Plant Diversity and Biogeography of East Asia; Kunming Institute of Botany; Chinese Academy of Sciences; Kunming 650201 China
4. UA Museum of the North and Department of Biology and Wildlife; University of Alaska Fairbanks; 907 Yukon Dr., PO Box 756960 Fairbanks AK 99775-6960 USA