Characterization of a new strain indicates that it is not a later synonym of .

The species Sesma and Ramirez was delineated based on the description of the single strain CBS 139.77. Based on its phenotypic similarities to , CBS 139.77 was later considered a synonym of . In the present study, we isolated the yeast strain IST 508 (=PYCC 8784=CBS 16671) from the soil surrounding an olive tree in Ferreira do Alentejo, Portugal. The phylogenetic analysis of D1/D2 domain and ITS sequences from strain IST 508 indicates that is closely related to . Although strain IST 508 differs from CBS 139.77 by 14 substitutions and 20 indels (6.6 % divergence) in the ITS sequence, no divergence was detected at the level of D1/D2 domain, mitochondrial small subunit rDNA, and cytochrome oxidase II sequences. On the other hand, strains IST 508 and CBS 139.77 differ from NRRL Y-17577 by eight substitutions (1.4 % divergence) in the D1/D2 domain sequence, by 16 substitutions (2.7 % divergence) in the cytochrome oxidase II sequence, and by 16 substitutions (3.7 % divergence) in the mitochondrial small subunit rDNA sequence. Due to the high number of variable phenotypic tests in and , strains from the two species are difficult to distinguish. Contrasting with what is described for other species, no differences were detected at the level of micromorphology between the two species. Nevertheless, based on the molecular differences between the two strains, CBS 139.77 and IST 508, and NRRL Y-17577 and their phylogenetic analysis, strains CBS 139.77 and IST 508 are from and this species should be considered as an independent species and not a later synonym of . We propose an emended description of .