The genus Tremella (Tremellales, Basidiomycota) in Russia with description of two new species and proposal of one nomenclatural combination

Twenty-two non-lichenicolous species of Tremella are reported from Russia. Detailed descriptions, photographs, illustrations and a dichotomous key for the identification of taxa are provided. Two species, Tremella subalpina and T. griseola, are described as new. One new combination is proposed, and an epitype for Tremella yokohamensis is designated. Molecular phylogenetic reconstructions are presented based on nrITS and nrLSU regions in Bayesian and likelihood analyses. Phylo-genetic data were strongly correlated with morphological data and were useful to delimit closely related species.