Botryobasidium bambusinum (Botryobasidiaceae, Cantharellales): a new species from Yunnan, Southwest China, based on morphology and phylogeny

Botryobasidium bambusinum sp. nov. was collected in Yunnan Province, China, is described here as a new species based on its morphology and phylogeny. In this study, the taxon Botryobasidium bambusinum is characterised by its resupinate, coriaceous conidiomata with a smooth, hypochnoid, rubiginous to slightly reddish-brown hymenial surface, a slightly thick-walled basal hyphae with simple septa, subcylindrical, septate subglobose to globose, slightly thick-walled conidia measuring as 7.2-9.5 x 7-9 mu m. Phylogenetic analyses of the new species were based on the internal transcribed spacer (ITS) and large subunit (nrLSU) of ribosomal DNA (rDNA) sequences. The phylogenetic tree indicated that the new species belonged to the genus Botryobasidium, and was closely related to B. gossypirubiginosum, B. rubiginosum and B. simile. Botryobasidium gossypirubiginosum differs from B. bambusinum by having a floccose to cotton conidiomata. Botryobasidium rubiginosum differentiates from B. bambusinum by having a cottony conidiomata, and ovoid to ellipsoid, larger conidia (14.5-16 x 10.5-12.5 mu m vs 7.2-9.5 x 7-9 mu m). Botryobasidium simile can be distinguished from B. bambusinum by having an ochraceous to fulvous conidiomata, and larger conidia (21.5-27 x 16-18 mu m vs 7.2-9.5 x 7-9 mu m). A detailed description, illustrations and phylogenetic analysis of the new species are provided.