Taxonomic study of Hydnoporia (Hymenochaetales, Hymenochaetaceae) in East Asia with two new species

The genus Hydnoporia (Hymenochaetales, Hymenochaetaceae) was first described by Murrill in 1907. However, species of Hydnoporia were subsequently reclassified into the genera Hymenochaete, Hymenochaetopsis, and Pseudochaete due to overlapping morphological characteristics, leading to multiple synonyms and confusion among researchers. Recent phylogenetic analyses based on multimarker datasets have clarified the diversity and relationships within Hydnoporia, but East Asian species remain underrepresented due to limited morphological data. To address this gap, we conducted a comprehensive morphological and phylogenetic analysis of East Asian Hydnoporia specimens using internal transcribed spacer (ITS) and translation elongation factor 1-alpha (tef1) regions. From 42 specimens, we identified six species, including two novel species, Hydnoporia orienticorrugata sp. nov. and Hydnoporia subtabacina sp. nov., and we report Hydnoporia rimosa for the first time in Korea. Phylogenetic analyses also support the recombination of Hymenochaete intricata and Hymenochaetopsis rigidula as Hydnoporia intricata comb. nov. and Hydnoporia rigidula comb. nov., respectively. By elucidating the phylogenetic relationships and morphological traits of Hydnoporia species from East Asia, this study contributes to a deeper understanding of the global diversity and phylogeny of the genus.