A new species and a new combination in Waitea (Corticiales, Basidiomycota) and the phylogenetic affinity of Disporotrichum

The new corticioid species Waitea guianensis was described and illustrated from French Guiana, based on morphological and molecular phylogenetic evidence. It was characterized by thin, resupinate basidiomata on wood, isodiametric subhymenial hyphae, lack of clamps, tetrasporic clavate basidia with median constriction, and ellipsoid basidiospores. Ex-holotype DNA sequences from the nuclear ribosomal regions ITS, nLSU, and nSSU were obtained. Phylogenetic analyses confirmed a close relationship of the new species to Waitea circinata. In addition, the new combination Waitea arvalis is proposed, based on Laetisaria arvalis. The monotypic genus Disporotrichum is revealed to belong in the Corticiales, Corticiaceae. A key to the accepted species in Waitea is provided.