Hygrophorus citrinofuscus: epitypification of a rare waxcap species from Central Europe and its transfer to the genus Neohygrocybe.

Abstract

Hygrophorus citrinofuscus is a striking and rarely reported grassland species originally described by J. Favre from the Swiss Alps. In absence of sequence data for the type specimen, a recent collection from Austria, which is well documented based on morphology and sequence data, is designated as the epitype of H. citrinofuscus to stabilise the species concept. Further collections from Austria and the Czech Republic are given. Morphologically similar species are discussed. Hygrophorus citrinofuscus is morphologically and phylogenetically well delimited and macroscopically characterised by yellow-brown pileus colours, a fibrillose pileus surface, pale lamellae and a yellow stipe, making it readily recognisable in the field. Morphology of the lamellar trama as well as phylogenetic analyses of a combined matrix of ITS, LSU, SSU and RPB2 sequence data clearly place this species in the genus Neohygrocybe, and a transfer is proposed. Citation: Friebes G, Fuljer F, Boertmann D, Voglmayr H, Kautmanová I (2025). Hygrophorus citrinofuscus: epitypification of a rare waxcap species from Central Europe and its transfer to the genus Neohygrocybe. Fungal Systematics and Evolution 15: 121-132. doi: 10.3114/fuse.2025.15.05.