A yeast strain belonging to the basidiomycetous yeast genus Cystofilobasidium was isolated from a marine sediment sample collected in an intertidal zone in Shandong province, PR China. The results of phylogenetic analyses based on sequences of the D1/D2 domain of the 26S ribosomal RNA gene and the internal transcribed spacer (ITS) region indicate that this strain, together with three other strains isolated from basal ice collected in Norway, the gut of an insect and an alga collected in Russia, represent a novel species of the genus, for which the name Cystofilobasidium josepaulonis sp. nov. (holotype strain CGMCC 2.6672T) is proposed. The novel species differs from the known species of the genus Cystofilobasidium by 1.7 %-4.1 and 11.3 %-17.1 % mismatches in the D1/D2 domain and the ITS region, respectively. This species forms teliospores on potato dextrose agar (PDA) and 10 % V8 juice agar, but teliospore germination with basidia was not observed.
Keywords: Cystofilobasidium; marine yeast; phylogeny; taxonomy.