Phylogeny of Verrucosporaceae (Basidiomycota, Agaricales): taxonomic novelties in Cystolepiota and Lepiota from China

The family Verrucosporaceae , a recently resurrected lepiotoid fungal lineage, has historically been subject to unstable generic delimitations and polyphyletic infrageneric classifications. To resolve these taxonomic ambiguities, we conducted comprehensive morphological examinations and multi-locus phylogenetic analyses (nrITS, nrLSU, rpb2 , and tef1-α ) based on extensive specimen sampling across China. Our results strongly support the monophyly of Verrucosporaceae and clarify the evolutionary boundaries among its core genera, including Cystolepiota , Echinoderma , Lepiota , Pulverolepiota , and Smithiomyces . Within Lepiota , seven formally defined sections and four unplaced distinct clades were recovered. A novel subsection, Lepiota sect. Eriophorae subsect. Pseudocystolepiotae , is proposed to accommodate an evolutionary transitional lineage between Cystolepiota and Lepiota sect. Eriophorae . Based on an integrative taxonomic approach, we describe 17 species new to science, introduce three new combinations, and reinstate Lepiota squamulosa . Furthermore, micromorphological observations indicate that the microstructure of the pileus and stipe coverings shares structural homology, reinforcing its reliability as a criterion for infrageneric delimitation. Ultimately, this study expands the current understanding of cryptic diversity within Verrucosporaceae in China and provides useful morphological and phylogenetic data for future evolutionary studies on lepiotaceous fungi.