A new species of Purpureocillium (Ophiocordycipitaceae) fungus parasitizing trapdoor spiders in Brazil's Atlantic Forest and its associated microbiome revealed through in situ "taxogenomics".

Our planet is inhabited by an estimated 2.5 million species of fungi, of which fewer than 10% have been scientifically described. Some of the most understudied yet remarkable fungal species are those capable of parasitizing arthropods, notably insects and spiders. Here, we explore the hidden diversity of a spider-attacking (araneopathogenic) fungus and its associated microbiome in one of the world's most biodiverse yet threatened biomes, the Atlantic Forest. We apply a field-based "taxogenomic" approach, comprising the integration of classical fungal taxonomy and genomic characterization of a sample's endogenous, associated, and incidental DNA. The data we produced in the field reveal a new species of Purpureocillium fungus belonging to the P. atypicola group, parasitizing trapdoor spiders, and provide a snapshot of its associated bacterial and fungal microbiota. Molecular, morphological, and ecological data support P. atypicola as a complex of cryptic species infecting a variety of ecologically distinct spider species globally. We call for consolidated efforts to accelerate and facilitate the publication of both new species and the characterization of the genomic composition of their associated taxa.