Abstract
Three strains (DMKU-RE28, DMKU-RE43(T) and DMKU-RE123) of a novel anamorphic yeast species were isolated from rice leaf tissue collected in Thailand. DNA sequence analysis demonstrated that the species forms a sister pair with Candida ranongensis CBS 10861(T) but differs by 24-30 substitutions in the LSU rRNA gene D1/D2 domains and 30-35 substitutions in the ITS region. A phylogenetic analysis based on both the small and the large rRNA gene subunits confirmed this connection and demonstrated the presence of a Glade that also includes Candida catenulata, Candida mesorugosa, Candida neorugosa, Candida pseudorugosa, Candida rugosa and Candida scorzettiae. The Glade is not closely affiliated to any known teleomorphic genus, and forms a well-separated lineage from currently recognized genera of the Saccharomycetales. Hence, the genus Diutina gen. nov. is proposed to accommodate members of the Glade, including Diutina siamensis f.a. sp. nov. and the preceding seven Candida species. The type strain is DMKU-RE43(T). (=CBS 13388(T)=BCC 61183(T)= NBRC 109695(T)).
