Species diversity of Clitocybaceae from Shanxi Province of northern China, with descriptions of seven new species

Clitocybaceae, currently recognized in the suborder Tricholomatineae, has undergone significant taxonomic reevaluation through phylogenetic, phylogenomic, and morphological analyses. In this study, we surveyed the species diversity of Clitocybaceae in Shanxi Province, northern China. Phylogenetic analyses were performed using ITS (internal transcribed spacer) and six loci including ITS, 28S (large subunit ribosomal), <i>tef1</i> (translation elongation factor 1-alpha), <i>rpb1</i> (DNA-directed RNA polymerase II largest subunit 1), <i>rpb2</i> (second largest subunit of RNA polymerase II), and <i>atp6</i> (adenosine triphosphate [ATP] synthase subunit 6). Comprehensive phylogenetic analyses revealed 20 Clitocybaceae species from our collections, which are distributed in four genera, i.e. <i>Collybia, Lepista, Pseudolyophyllu.m</i>, and <i>Singerocybe</i>. Combined with morphological characteristics, 13 of them were identified as known species and seven were described and illustrated as new species in this paper. These findings significantly contribute to our understanding of Clitocybaceae diversity and taxonomy in northern China.