Kazachstania ichnusensis sp. nov., a diploid homothallic ascomycetous yeast from Sardinian lentisk rhizosphere.

During an investigation of yeast biota in the rhizosphere of lentisk in Sardinian semi-arid areas, a strain was isolated that could not be assigned to any known species. The sequence of the D1/D2 domain of the large subunit rDNA gene revealed that the strain belonged to the genus Kazachstania and was phylogenetically related to a clade including Kazachstania aerobia, Kazachstania servazzii, Kazachstania solicola and Kazachstania unispora. The novel isolate differed from members of this clade in its ability to assimilate D-glucono-1,5-lactone and its very weak fermentation of glucose and sucrose; its assimilation profile was unique within the genus Kazachstania. Monosporal colonies were able to sporulate, indicating that the species is homothallic. It is proposed that the isolate represents a novel species, Kazachstania ichnusensis sp. nov., with LCF 1675(T) (=CBS 11859(T)) as type strain.