Multigene phylogeny and taxonomy of Hydnaceae (Cantharellales, Basidiomycota) reveal Leucopruina abieticola gen. et sp. nov. from Southwest China.

During a survey of wood-decaying fungi in the subalpine forests of Southwest China, distinctive corticioid specimens were collected from fallen Abies trunks. Based on a combination of morphological characteristics and multigene phylogenetic analyses of the internal transcribed spacer (ITS) and nuclear large subunit (nLSU) sequences, these specimens were found to represent a highly distinct and strongly supported monophyletic lineage within the family Hydnaceae (Order: Cantharellales; Division: Basidiomycota). Consequently, a new genus, Leucopruina gen. nov., is proposed to accommodate the novel species L. abieticola sp. nov. Morphologically, the new species is characterized by its white, pruinose, resupinate basidiomata and a dimitic hyphal system with branched skeletal hyphae. Although it shares urniform basidia bearing 6-8 sterigmata with Sistotremella, Leucopruina is clearly distinguished by its thin-walled, acyanophilous (CB-) basidiospores, in contrast to the thick-walled, cyanophilous (CB+) spores of Sistotremella. This discovery increases the number of recognized genera within Hydnaceae to 19 and highlights the rich but previously underestimated taxonomic diversity of saprotrophic fungi in the high-altitude ecosystems of Southwest China.