Amanita in the Rocky Mountain Alpine zone, USA: New records for A. Nivalis and A. Groenlandica

Abstract

A limited number of Amanita species have been reported from cold dominated arctic-alpine environments, primarily with dwarf and shrub willows. This includes reports from Alaska, Canada, Greenland, Iceland, Scandinavia, Scotland, the Alps, and Russia. Here we report Amanita nivalis, A. groenlandica f. alpina n. f. and A. vaginata above tree line in the Rocky Mountains with Salix reticulata, S. nivalis, S. glauca, and S. planifolia. The distribution of Amanita groenlandica is extended to the north-central Rockies, and more definitively to the Beartooth Plateau at 3,100 to 3,400 m a.s.l. A new alpine form is described for this arctic species. Amanita nivalis is confirmed from numerous cirques and high passes 3,600-3,900 m a.s.l. in the southern Rocky Mountains (Front Range, Sawatch Range, San Juan Mountains), adding a disjunct component to its circumpolar distribution. These localities are thousands of miles from the Arctic and are likely near the southern-most extent of its distribution in North America. Rocky Mountain species are reported in context with arctic-alpine Amanita species from the Northern Hemisphere. © 2010 Pacific Northwest Fungi Project.