Description of gen. nov., sp. nov., sp. nov. and sp. nov., and genome-based taxonomy of genera and .

Three extremely halophilic archaeal strains (LT55, SQT-29-1 and WLHS5) were isolated from Gobi saline soil and a salt lake, China. These strains were most related to the genera and (92.6-95.1 % similarities), and showed low similarities with other genera within the family based on 16S rRNA genes. Phylogenomic analysis confirmed that the three strains formed a distinct clade separated from the related genera and , which indicated that they may represent a novel genus of the family . The average nucleotide identity (ANI), in silico DNA-DNA hybridization (DDH) and average amino acid identity (AAI) values among the three strains were no more than 87, 34 and 85 %, respectively, much lower than the threshold values for species demarcation. The major phospholipids of the three strains were phosphatidic acid (PA), phosphatidylglycerol (PG) and phosphatidylglycerol phosphate methyl ester (PGP-Me). The glycolipid profiles of the three strains were diverse; sulfated mannosyl glucosyl diether (S-DGD-1) and disulfated mannosyl glucosyl diether (S-DGD) were found in strains LT55 and WLHS5, while mannosyl glucosyl diether (DGD-1) and S-DGD-1 in strain SQT-29-1. The combination of phenotypic, chemotaxonomic, phylogenetic and genomic analyses suggested that strains WLHS5 (=CGMCC 1.13781 = JCM 33558), SQT-29-1 (=CGMCC 1.16065 = JCM 33554) and LT55 (=CGMCC 1.15188 = JCM 30838) represent three novel species of a new genus within the family , for which the names, gen. nov., sp. nov., sp. nov. and sp. nov., are proposed. Genome-based classification of genera and revealed that should be transferred to the genus as comb. nov. and as a heterotypic synonym of Liu . 2015.