Two new species of Hygrocybe subg. Hygrocybe (Hygrophoraceae, Agaricales) from southeast China

The genus Hygrocybe is a species-rich group of macrofungi widely distributed across the world; however, species within this genus show high morphological variability and significant regional differences, and taxonomic revisions are ongoing. In this study, based on specimens from Anhui and Jiangxi provinces, China, we describe two previously unreported species, Hygrocybe zhibaiensis and H. longchuanensis , using morphological studies and phylogenetic analyses based on internal transcribed spacer (ITS) and large subunit ribosomal (LSU) sequences. Hygrocybe zhibaiensis is characterized by viscid basidiomata, a greenish pileus, a stipe that is bright yellow at the apex and gradually fades to white downwards, and basidiomata that turn black upon bruising or with age; H. longchuanensis is characterized by a bright red pileus at the center with an orange-yellow margin, a viscid surface, and an orange-yellow to yellow stipe, Basidiospores ellipsoid to subglobose, no clamp connections. This discovery enriches the diversity of Hygrocybe in southeastern China and contributes to the taxonomic research of this genus.