Circinariarussus sp. nov. (Lichenized Ascomycota: Megasporaceae) from Pakistan.

Circinaria russus sp. nov. is described based on morpho–anatomical and phylogenetic analysis. The novel species is characterized by its reddish brown thallus, absence of marginal lobes, taller hymenium 175–190 µm, and larger ascospores 22–32 × 15–20 than the similar taxon Circinaria tortuosa. A phylogenetic analysis, based on ITS nrDNA sequencing and ML analysis, supported the separation of the novel species. Complete description and a comparative analysis with related Circinaria species are provided. [ABSTRACT FROM AUTHOR]