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

The genus <i>Hydnoporia</i> (Hymenochaetales, Hymenochaetaceae) was first described by Murrill in 1907. However, species of <i>Hydnoporia</i> were subsequently reclassified into the genera <i>Hymenochaete</i>, <i>Hymenochaetopsis</i>, and <i>Pseudochaete</i> 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 <i>Hydnoporia</i>, 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 <i>Hydnoporia</i> specimens using internal transcribed spacer (ITS) and translation elongation factor 1-α (<i>tef1</i>) regions. From 42 specimens, we identified six species, including two novel species, <i>Hydnoporiaorienticorrugata</i> <b>sp. nov.</b> and <i>Hydnoporiasubtabacina</i> <b>sp. nov.</b>, and we report <i>Hydnoporiarimosa</i> for the first time in Korea. Phylogenetic analyses also support the recombination of <i>Hymenochaeteintricata</i> and <i>Hymenochaetopsisrigidula</i> as <i>Hydnoporiaintricata</i> <b>comb. nov.</b> and <i>Hydnoporiarigidula</i> <b>comb. nov.</b>, respectively. By elucidating the phylogenetic relationships and morphological traits of <i>Hydnoporia</i> species from East Asia, this study contributes to a deeper understanding of the global diversity and phylogeny of the genus.