Khargia gen. nov., a new genus of simple trichal Cyanobacteria from the Persian Gulf

Abstract

Information regarding the diversity of Cyanobacteria in many parts of the world is still minimal. One example of a region that has not yet been widely studied is south–western Asia, including the region of the Persian Gulf. A culture–dependent study of cyanobacterial diversity in a rainwater basin on Kharg Island enabled the isolation of a novel taxon, previously unnamed, from a simple trichal cyanobacterium. Further comparisons showed the existence of closely related strains/taxa from other parts of the world, namely the strains CCALA 945 isolated from South Italy and “Leptolyngbya india” from India. Herein, we have thus described the new genus Khargia and the new species Khargia iranica. Other strains, isolated by other authors, were included in the Khargia genus as additional species: Khargia italica and Khargia indica. The recognition of the new genus was based on morphological evaluations (identification by both light and electron microscopy), the phylogenetic analyses based on the 16S rRNA gene, and species delimitation based on Automatic Barcode Gap Definition (ABGD), Generalized Mixed Yule Coalescent (GMYC), bayesian version of Poisson Tree Processes (bPTP), and the secondary structure of 16S–23S rRNA ITS region of the studied strains.