Abstract
Species of the basidiomycetous genus Tomentella are widely distributed throughout temperate forests. Numerous studies on the taxonomy and phylogeny of Tomentella have been conducted from the temperate zone in the Northern hemisphere, but few have been from subtropical forests. In this study, four new species, T. casiae, T. guiyangensis, T. olivaceomarginata and T. rotundata from the subtropical mixed forests of Southwestern China, are described and illustrated based on morphological characteristics and phylogenetic analyses of the internal transcribed spacer regions (ITS) and the large subunit of the nuclear ribosomal RNA gene (LSU). Molecular analyses using Maximum Likelihood and Bayesian analysis confirmed the phylogenetic positions of these four new species. Anatomical comparisons among the closely related species in phylogenetic and morphological features are discussed. Four new species could be distinguished by the characteristics of basidiocarps, the color of the hymenophoral surface, the size of the basidia, the shape of the basidiospores and some other features.