A review of the genus Hebeloma in Svalbard

Between 1960 and 2009, regular visits to Svalbard were made and a number of Hebeloma spp. were collected by several mycologists. We have studied 249 such collections, many from the Herbarium in Oslo (O) and from the private herbarium of the first author. The collections represent 17 different species. Of the 17 species, five (H. louiseae, H. pallidolabiatum, H. perexiguum, H. pubescens and H. spetsbergense) are only known from Svalbard. In this paper we discuss the habitat and apparent associates of the 17 species recorded, as well as their frequency of occurrence within our sample, and compare this with our data from other regions of the northern hemisphere. A further analysis compares the records we have from the collection of basidiomes with data published from root analysis of mycorrhizal associates on Svalbard. Root associate data strongly suggest the occurrence of an unknown Hebeloma species, not close to any of the infrageneric groups known to occur in arctic habitats.