Diversity of basidiomycetous phylloplane yeasts belonging to the genus Dioszegia (Tremellales) and description of Dioszegia athyri sp. nov., Dioszegia butyracea sp. nov. and Dioszegia xingshanensis sp. nov.

From approximately 200 basidiomycetous yeast isolates forming orange or orange-red colonies isolated from senescent leaves collected in different regions of China, 29 representative strains varying in their geographic distribution and ballistoconidium forming ability were selected for further phenotypic and molecular taxonomic studies. Sequence analysis of the large subunit (26S) rDNA D1/D2 domain and the internal transcribed spacer (ITS) region including 5.8S rRNA from the strains resulted in the recognition of seven Dioszegia species, including four described species, namely D. aurantiaca, D. fristingensis, D. hungarica and D. zsoltii var. zsoltii and D. zsoltii var. yunnanensis, and three undescribed species. The three new species are described as Dioszegia athyri sp. nov. (type strain: CB 159(T) = AS 2.2559(T) = CBS 10119(T)), Dioszegia butyracea sp. nov. (type strain: CB 261(T) = AS 2.2600(T) = CBS 10122(T)) and Dioszegia xingshanensis sp. nov. (type strain: HB 1.4(T) = AS 2.2481(T) = CBS 10120(T)) in the present study.