Taxonomic and phylogenetic contributions to (Hymenochaetales, Basidiomycota): two new species from Hawaii with a key to North American species.

is a cosmopolitan, poroid, wood-decaying genus, belonging to the Hymenochaetales. During a study of wood-inhabiting fungi in the USA, four unknown specimens were collected from Hawaii. Both morphological criteria and molecular genetic analyses based on the ITS+nLSU+EF1-α datasets and the nLSU dataset confirmed that these four specimens represent two new species of , and they are described as and is characterized by pileate basidiocarps, the absence of cystidioles, hooked hymenial setae, broadly ellipsoid to subglobose basidiospores measuring 4-6 × 3.5-4.5 μm. is distinguished by small pores (10-13 per mm) and basidiospores (3.4-4 × 2.4-3 μm). The taxonomic status of the two new species is briefly discussed. A key to the North American species of is provided.