1. National Centre for Biosystematics; Natural History Museum; University of Oslo; P.O. Box 1172 Blindern 0318 Oslo Norway
2. Centre for Ecological and Evolutionary Synthesis; Department of Biology; University of Oslo; P.O. Box 1066 Blindern 0316 Oslo Norway
3. Department of Botany; St. Petersburg State University; St. Petersburg Russia
4. Botanical Garden and Museum; Natural History Museum of Denmark; University of Copenhagen; Gothersgade 130 1123 Copenhagen K Denmark