This work is part of the survey about polyporoids xylophagous fungi from the Araucária wood of the Aparados da Serra Nacional Park, RS. It includes the species of two closely related genera Rigidoporus and Flaviporus that occur in this area. The genera Rigidoporus is represented for three species: R. lineatus (Pers.) Ryv, R. ulmarius (Sow. ex Fr.) Imazeki and R. umbonatipes Rajch- The latter is a new citation for Brazil. The genus Flaviporus is also represented for three species: R. subhydrophilus (Speg.) Rajch. & Wright, F. venustus David & Rajch, and Flaviporus sp. Keys for identification, descriptions, remarks and ilustrations of each species are presented.
Rigidoporus; Flaviporus; Systematics; Basidiomycetes