Cartusia hunanesis sp. nov. (Oculatellaceae, Oculatellales) from a Stream in China Based on Polyphasic Approach

Cartusia hunanesis sp. nov. was isolated from a stream in China, and two strains (ZJJ02 and ZJJ03) of which were inquired using morphological features, ecological evidence, and molecular data consisting of the 16S rRNA gene and 16S-23S rRNA intergenic transcribed spacer (ITS) region. Cartusia hunanesis varies from the type species Cartusia fontana by having only a single trichome in the sheath and large granules near the cross wall. The investigated strains of C. hunanesis were revealed to be a sister clade of C. fontana, according to the phylogenetic analysis based on the 16S rRNA gene. In addition, the Cartusia was clustered with the family Oculatellaceae members, genera Pegethrix and Elainella. These two strains displayed 97.6% similarity to C. fontana. The ITS region of C. hunanesis was found to be considerably distinct from that of C. fontana in terms of the secondary structure, which demonstrated that C. hunanesis is a novel species owing to the divergences in its morphological and genetic data compared with the related C. fontana.