Pluteus canaliculatus (Pluteaceae: Agaricomycetes), a new species of Pluteus section Celluloderma from Turkey

During a survey of the macrofungal diversity in the Sweetgum Forest Nature Protection Area (Burdur Province), southwestern Turkey, we discovered a new species of Pluteus. The species is described and illustrated here as Pluteus canaliculatus, based on its morphological characteristics and molecular phylogenetic analyses. The new species was found on wood in a Liquidambar orientalis forest and is characterized by a light brown-yellow to reddish brown canaliculate pileus, ochre brown lamellar edges, a shiny, silvery cream stipe, predominantly ellipsoid basidiospores, mostly narrowly fusiform to fusiform pleurocystidia, often with a moniliform to flexuose neck, and an euhymeniderm or a transitional (hymeniderm and epithelium) type of pileipellis. Phylogenetic analyses of nuclear ribosomal internal transcribed spacer ITS1-5.8S-ITS2 (ITS) region sequences reveal that Pluteus canaliculatus belongs to Pluteus sect. Celluloderma, forming a distinct lineage in the /thomsonii clade. A description and a comparison with morphologically similar and closely related species are provided, together with colour photographs and line drawings of the species.