During surveys in the Brazilian Amazon, Atlantic Forest and Caatinga, several species of poroid Hymenochaetaceae were collected. Of the collected specimens, ITS and LSU sequences were generated and phylogenetic analyses performed. From morphological and phylogenetic inferences, Sclerotus Xavier de Lima, gen. nov. is described based on collections of Phellinus extensus, while Inonotus parvisetus V.R.T. Oliveira, Xavier de Lima & Gibertoni, sp. nov., Tropicoporus flabellatus V.R.T. Oliveira, J.R.C. Oliveira-Filho, Xavier de Lima & Gibertoni, sp. nov and T. nullisetus Xavier de Lima, V.R.T. Oliveira & Gibertoni, sp. nov. are described as new species. Sclerotus gen. nov. is characterized by the strongly ventricose hymenial setae and the black line that is exposed as a dark crust. Inonotus parvisetum can be differentiated from similar species of the genus by the smaller tramal setae. Tropicoporus flabellatus sp. nov. produces the thinnest basidiomata in the genus, and does not develop a dark crust in the pileus surface, while in T. nullisetus sp. nov. hymenial setae is absent. The other specimens clustered within I. micantissimus (Rick) Rajchemb., I. rickii (Pat.) Reid, T. linteus (Berk. & M.A.Curtis) L.W.Zhou & Y.C.Dai, T. stratificans G.Coelho & Yurchenko and T. tropicalis (M.J.Larsen & Lombard) L.W.Zhou & Y.C.Dai. Here T. stratificans is recorded for the first time outside the type locality. Illustrations of the species and keys for Inonotus sensu lato are provided.
Amazon, Atlantic Forest, Agaricomycetes, Neotropics, Poroid fungi, new genus, new species