Natonodosa speciosa gen. et sp. nov. and rediscovery of Poroisariopsis inornata : neotropical anamorphic fungi in Xylariales

Natonodosa is introduced as new genus based on morphology and multigene phylogenetic data, and the monotypic genus Natonodosa , typified by N. speciosa , is characterized by mononematous conidiophores, polyblastic, nodose conidiogenous cells and unicellular, fusiform, hyaline conidia. The other freshly collected material was identified as Poroisariopsis inornata , a species that since its original description had not been reported; it is characterized by synnematous conidiophores with polytretic, cylindrical and uncinate conidiogenous cells with percurrent extensions, and distoseptate, obclavate, brown conidia. A lectotype and an epitype for the species are established and referred since the original specimen of this microfungus has not been found in any herbarium. Placement of both taxa in Xylariales was ascertained by BLASTn searches. Maximum likelihood analysis of the combined sequence data of the ribosomal rDNA (ITS and partial LSU region), as well as partial gene regions coding for the second largest subunit of RNA polymerase II ( RPB2 ) and beta-tubulin ( TUB2 ), was performed. In addition, a new name, Guarroa , is proposed for replacing the illegitimate genus name Phaeobotrys M. Calduch, Gené & Guarro . A dichotomous key to the new genus and morphologically similar taxa is provided.