Taxonomy and phylogeny of the ascomycetous yeast genus Zygoascus, with proposal of Zygoascus meyerae sp. nov. and related anamorphic varieties.

Physiological characters, mating compatibility, PCR-RAPD fingerprints, mol% G + C content, DNA-DNA relatedness, and large-subunit and internal transcribed spacer rRNA gene sequences of strains assigned to the genus Zygoascus were re-examined. On the basis of those data, and after phylogenetic analyses, an emendation of Zygoascus hellenicus (type material is a cross of CBS 6736(T) x CBS 5839(T)) is proposed, comprising two novel anamorphic varieties, Candida steatolytica var. steatolytica (CBS 6736(T)) and C. steatolytica var. inositophila (CBS 5839(T)). A novel teleomorphic species, Zygoascus meyerae sp. nov. (type material is a cross of CBS 4099(T) x CBS 7521(T)) is described, together with two novel anamorphic varieties corresponding to it, Candida hellenica var. hellenica (CBS 4099(T)) and C. hellenica var. acidophila (CBS 7115(T)).