Three new wood-inhabiting fungi of Botryobasidium (Cantharellales, Basidiomycota) from subtropical forests of Southwestern China.

The basidiomycete genus Botryobasidium is a resupinate saprotrophic with a global distribution range from coniferous to broad-leaved forest ecosystems. Though numerous species have been reported from Eurasia and North America, few have been described from China. In the current work, phylogenetic analyses of Botryobasidium in China were conducted based on the dataset of the internal transcribed spacer (ITS) regions and the large subunit (LSU) of nuclear ribosomal RNA gene. Maximum likelihood and Bayesian analyses were used to reconstruct the phylogenetic tree, and three new species, namely Botryobasidiumacanthosporum, B.leptocystidiatum and B.subovalibasidium, were described from subtropical forests of Yunnan Province, Southwestern China. Botryobasidiumacanthosporum is characterized by having yellowish white to dark yellow basidiome, clavate to tubular cystidia, and subglobose to globose basidiospores with obtuse spines. Botryobasidiumleptocystidiatum is characterized by having fluffy to arachnoid, greyish white to ivory basidiome, generative hyphae with clamped, tubular cystidia, and subnavicular to navicular basidiospores. While, B.subovalibasidium is characterized by having yellowish to ivory basidiome, subovoid basidia, navicular to suburniform basidiospores, and thick-walled chlamydospores. These three new species are described and illustrated, and the discriminating characters between the new species and their closely related species are discussed. A key to known species of Botryobasidium in China is provided.