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

<i>Brasilioporus olivaceoflavidus</i>, gen. et sp. nov., <i>Brasilioporus simoniarum</i>, sp. nov., <i>Neotropicomus australis</i>, gen. et sp. nov., and <i>Nevesoporus nigrostipitatus</i>, 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 <i>Xerocomus parvogracilis, Tylopilus rufonigricans</i>, and <i>Tylopilus exiguus</i>. Boletaceae subfamily Chalciporoideae was recircumscribed to include the new genus <i>Nevesoporus</i>. Molecular phylogenetic analyses using a multilocus data set (ITS+28S+<i>TEF1</i>+<i>RPB1</i>+<i>RPB2</i>) 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.