Multiple phylogenies reveal a true taxonomic position of Dulcicalothrix alborzica sp. nov. (Nostocales, Cyanobacteria)

Abstract

A new species of heterocytous cyanobacterium Dulcicalothrix alborzica sp. nov. (Calotrichaceae) was isolated from Iran and described following a polyphasic approach. Morphological examination indicated that the strain, initially called "Alborzica", belonged to the genus Calothrix. Nonetheless, 16S rRNA gene analysis showed that "Alborzica" were within the Dulcicalothrix cluster. In order to confirm the taxonomic position of this new taxon, rbcL and rpoC1 phylogenies were inferred. Results confirmed identity of "Alborzica" supporting the 16S rRNA phylogeny. Analysis of the secondary structures of 16S-23S Internal Transcribed Spacer (ITS) revealed that "Alborzica" had unique structure compared with known Dulcicalothrix spp. Therefore, based on the morphology and thorough molecular analysis, "Alborzica" should be considered a novel species in the genus Dulcicalothrix.