Morphological and phylogenetic analyses revealed Cystidichaete alba gen. et sp. nov. (Phanerochaetaceae, Polyporales) from Southwest China

Wood-inhabiting fungi are a remarkably diverse group that play a fundamental role in ecosystem processes, particularly in wood degradation and the recycling of organic matter. As pivotal contributors to the intricate balance of forest ecosystems, these fungi are renowned as “key players” for their enzymatic prowess and products, which effectively breaks down woody components such as lignin, cellulose, and hemicelluloses. In the present study, a new wood-inhabiting fungal genus Cystidichaete , with its type species C. alba , collected from southwest China, is proposed based on a combination of morphological features and molecular evidence. The new genus Cystidichaete is characterized by the resupinate basidiomata with a smooth hymenophore, a monomitic hyphal system with clamped generative hyphae, abundant lamprocystidia, clavate basidia, and ellipsoid basidiospores. Sequences of the internal transcribed spacers (ITS), nuclear large subunit ribosomal RNA (nLSU), RNA polymerase second largest subunit ( rpb2 ) and translation elongation factor 1-α ( tef1-α ) of the nuclear ribosomal DNA (rDNA) markers of the studied samples were generated. Phylogenetic analyses were performed using maximum likelihood, maximum parsimony, and Bayesian inference. Multi-locus phylogenetic analysis of ITS+nLSU+ rpb2 + tef1-α showed that Cystidichaete forms a monophyletic clade within the family Phanerochaetaceae (Polyporales), in which the new genus was grouped closely to Stereophlebia and Gelatinofungus .