1. Department of Botany, MRC-166; Smithsonian Institution; PO Box 37012 Washington DC 20013-7012 USA
2. UA Museum of the North and Department of Biology and Wildlife; University of Alaska Fairbanks; 907 Yukon Dr. PO Box 756960 Fairbanks Alaska 99775-6960 USA
3. Department of Systematics, Biodiversity and Evolution of Plants, Albrecht-von-Haller Institute of Plant Sciences; University of Göttingen; Untere Karspüle 2 37073 Göttingen Germany