Аннотация:A systematic survey for myxomycetes was carried out in three regions of the Kamchatka peninsula (Russian Federation), all belonging to the National Park “Vulkany Kamchatki”: A) around the Avachinsky volcano in southeastern Kamchatka (moist deciduous forests and subalpine shrub thickets); B) around Esso (dry larch forests); C) slopes of the Nikolka volcano (moist spruce forests). The latter two regions are situated in central Kamchatka. A total of 1389 records was determined to species. Of these, 1091 came from field collections and 298 were obtained from 245 moist chamber cultures prepared with samples taken from the bark surface of living trees, ground litter, coarse woody debris and weathered dung of cow and moose. Most (159) of the 170 taxa from 41 genera and 13 families were new for Kamchatka; 3 were new for Russia (Comatricha fragilis, Cribraria pertenuis, and Physarum bogoriense). Over two thirds (120 of 170) of taxa were classified as rare. A pattern of decreasing diversity with increasing elevation was found. The taxonomic composition of myxomycete assemblages of lowland poplar, spruce and larch forests was more diverse than that of montane shrub alder and dwarf pine thickets, and species diversity increased from dung, bark and ground litter to wood. We obtained 18S rDNA barcodes for 167 specimens from 85 taxa, with 9 species and 1 form not barcoded before; 102 of these barcodes represented new sequence variants
