Abstract
A pyrenochaeta-like species was isolated from soil in rice farms in Mazandaran Province (formerly Tabarestan), Iran. Phylogenetic analyses of SSU, LSU, ITS, β-tubulin and actin sequence data showed that the new collection clustered with species in Pyrenochaetopsis sensu stricto. In morphology, phylogeny and physiological characters, the new strains are distinct from other species, thus, they are introduced as a new species viz. P. tabarestanensis. Illustrations, descriptions and taxonomic notes are provided for P. tabarestanensis. Additionally, the phylogenetic relationships of Pyrenochaeta and Pyrenochaetopsis species in Cucurbitariaceae is discussed.