New genera, species, and combinations of Boletaceae from Brazil and Guyana.

Brasilioporus olivaceoflavidus , gen. et sp. nov., Brasilioporus simoniarum , sp. nov., Neotropicomus australis , gen. et sp. nov., and Nevesoporus nigrostipitatus , gen. et sp. nov. (Boletaceae, Boletales, Basidiomycota), are described from the endangered Atlantic Forest biome of eastern Brazil. New combinations into these new genera are proposed for the Guyanese taxa Xerocomus parvogracilis, Tylopilus rufonigricans , and Tylopilus exiguus . Boletaceae subfamily Chalciporoideae was recircumscribed to include the new genus Nevesoporus . Molecular phylogenetic analyses using a multilocus data set (ITS+28S+ TEF1 + RPB1 + RPB2 ) from a large taxon set across the Boletaceae justify recognition of the new genera. Morphological, ecological, and DNA sequence data are provided for the new species. A key to known native and introduced bolete species from the Brazilian Atlantic Forest is provided.