Description of the new species Tricholomopsis badinensis (Fungi). Tricholomopsis badinensis sp. nov. and T. sulphureoides – two rare fungi of European old-growth forests

Interesting Tricholomopsis collections from old-growth forests in Slovakia and Poland were studied morphologically and molecularly, using the rDNA fragment containing ITS1 and ITS2 regions, the 5.8S subunit, and the D1/D2 region of the 28S subunit. The phylogenetic analysis contains all hitherto sequenced Tricholomopsis species and shows a geographic pattern as species distributed primarily in Holartic are separated from those occurring primarily in the Southern Hemisphere. Tricholomopsis decora proved to be a species complex in which the new European species T. badinensis is published, based on collections from fallen trunks of silver fir (Abies alba) in Badínsky prales virgin forest. Rich collections of T. sulphureoides from Białowieża virgin forest are described and distribution and ecology of the species is summarized. Biological value of the two localities plus the Dobročský prales virgin forest, Slovakia, is documented by enumeration of fungal indicators of old-growth forests occurring there. A preliminary key for identification of European Tricholomopsis species lacking red or violet colour is created.