Edna de A. Silva

Two strains of Scopulariopsis -like fungi were isolated from the dorsal region of a live bat ( Glossophaga soricina , nectarivore species) captured inside Gruta do Arnoud, a cave in the Caatinga biome of northeastern Brazil. These isolates presented unique morphological features, and achieving a consensus identification at the species level proved to be challenging. Phylogenetic analysis, based on nucleotide sequences from the internal transcribed spacer, large subunit ribosomal RNA gene, translation elongation factor 1-alpha ( tef1 ) and beta-tubulin ( tub2 ) genes, confirmed that these fungi represent previously undescribed species within the genus Microascus . The new species is named Microascus luziarum URM 9260. Phylogenetically, they grouped in a clade closely related to Microascus brunneosporus , Microascus micronesiensis and Microascus chinensis , but distinct differences were observed. Morphologically, the new species could be differentiated by their distinctive characteristics, such as reduced growth on oatmeal agar medium, reaching 15 mm after 14 days at 25 °C. Microscopically, it differs in the size of the conidiophores, which are shorter and broader compared to M. brunneosporus and M. micronesiensis . Additionally, it presents globose to subglobose conidia with diameters larger than those observed in closely related species. The use of a four-marker combination was an efficient approach to support the taxonomic novelty. This discovery enhances the understanding of Microascus diversity, particularly within cave ecosystems, and emphasizes the potential for discovering new fungal species in such specialized environments.