Pluteus rugosidiscus (Basidiomycota, Pluteaceae), first record of this North American species in Europe. Pluteus rugosidiscus (Basidiomycota, Pluteaceae), first record of this North American species in Europe

The first record of Pluteus rugosidiscus from Europe (Slovakia) is published. The pileipellis structure in this species indicates its placement in section Celluloderma subsection Eucellulodermini. According to a phylogenetic analysis (ITS rDNA), Pluteus rugosidiscus forms a sister clade to the complex of P. chrysophlebius and represents a distinct species. In several collections, sequences of the molecular markers LSU, EF-1α and RPB2 were obtained. These were not included in the phylogenetic tree, but used for a comparison confirming P. rugosidiscus as a separate species. Pluteus rugosidiscus is macroscopically characterised by a pileus with a green hue and a yellow stipe; microscopically by lageniform to fusiform pleurocystidia. It is particularly similar to the taxa of the P. chrysophlebius complex and in some cases may represent a cryptic species.