Multiple evidences reveal new species and a new record of smelly Gymnopus (Agaricales, Omphalotaceae) from China

Gymnopus sect. Impudicae is a poorly studied group around the world. However, it is well known for its pungent smell-a total of five species from China belonging to sect. Impudicae were recorded, and included four species new to science-G. epiphyllus, G. cystidiosus, G. subdensilamellatus, and G. subpolyphyllus-which were delimited and proposed based on morphological and molecular evidences, and one new record from Henan, Jiangxi, and Gansu Province, China-G. densilamellatus. Detailed descriptions and illustrations were presented as well as comparisons to similar species. Phylogenetic analysis inferred from the ITS and nLSU dataset supported the Gymnopus as a monophyletic genus which was defined by Oliveira et al., and the novel species grouped as separate lineages within it. A Key to the reported species of Gymnopus sect. Impudicae is also provided.