Calvelo, SusanaStocker-Worgotter, ElfieLiberatore, SandraElix, John2015-12-132015-12-130093-4666http://hdl.handle.net/1885/77019Protousnea fibrillatae from south-western Argentinean Nothofagus forests, is described as new to science. While the apothecia are typical of Protousnea, this new species is characterized by the presence of fibrils, a character previously unknown in the genus. The meta-depsides, subsekikaic and 4′-O-demethylsekikaic acids are reported the first time for Protousnea.Keywords: Ascomycota; Nothofagus; Parmeliaceae; Protousnea 4'-O-demethylsekikaic acid; Nothofagus forest; Patagonia; Protousnea fibrillatae; Subsekikaic acid20032015-12-11