Revision of sections and : Assessment of species boundaries, determination of mating-type loci, and identification of Russian strains.

is a large genus within Pleosporaceae and consists of fungi that have up to recently been considered to be 15 separate genera, including . The majority of species after incorporation into were placed in three sections: , and . In this study, phylogeny of 26 reference strains of 22 species and 20 Russian -like isolates was recovered. The partial actin gene (), major allergen (), calmodulin (), glyceraldehyde-3-phosphate dehydrogenase (), RNA polymerase II second largest subunit (), and translation elongation factor 1-α () were sequenced for Russian isolates. All these fungi were examined using multilocus phylogenetic analysis according to the genealogical concordance phylogenetic species recognition (GCPSR) principle and the coalescent-based model Poisson tree processes (PTP, mPTP) and evaluated for the presence of recombination. All strains were combined into two clades that corresponded to the and sections. The clade included four reference strains and nine local isolates and considered to be a single species, whereas the section comprises 11 species, instead of 17 names previously adopted. Nine species were abolished by joining four other species. Species and were combined into the single species . Five species, , and , were united in the species and were combined into one species, , and were combined into a single species, . Also, amplification with two different primer sets was performed to define mating-type locus 1 () idiomorph. All studied isolates were heterothallic, contradicting some prior studies. Twenty Russian -like isolates were assigned to five species of two sections, , and . Species and were found in Russia for the first time.