Revision of collections of Hebeloma spp. from the high-altitude Altay Mountains (Altay Republic) and report of a new to Russia species of H. excedens

Eight Hebeloma specimens from the high-altitude zone of Altai Mountains (West Siberia) were analyzed using morphological and molecular methods. Three species were identified (H. alpinum, H. dunense, H. excedens), including the previously unreported in Russia species H. excedens. The detailed morphological description and ecological data on H. excedens based on the studied collections are provided.