A novel Gram-staining-negative, non-pigmented, rod-shaped, strictly aerobic, extremely halophilic bacterium, designated strain IA16T, was isolated from saline mud of the hypersaline lake Aran-Bidgol in Iran. Cells of strain IA16T were not motile. Growth occurred between 2.5 and 5.2 M NaCl and optimally at 3.4 M NaCl. The optimum pH and temperature for growth of strain IA16T were pH 7.0 and 40 °C, respectively, while it was able to grow at pH and temperature ranges of 6.0-8.0 and 30-50 °C, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain IA16T is a member of the family Rhodospirillaceae; however its similarity was as low as 91.6 %, 88.9 % and 88.7 % to the most closely related taxa including Rhodovibrio, Pelagibius and Fodinicurvata type species, respectively. The major cellular fatty acids of the isolate were C19:0 cyclo ω7c and C18:0. The polar lipid pattern of strain IA16T consisted of phosphatidylglycerol, diphosphatidylglycerol, four phospholipids, three aminolipids and two unknown lipid components. The cells of strain IA16T contained the ubiquinone Q-10. The G+C content of the genomic DNA of this strain was 67.0 mol%. The physiological, biochemical and phylogenetic differences between strain IA16T and other previously described taxa suggest that this strain represents a novel species in a new genus within the family Rhodospirillaceae, for which the name Limimonas halophila gen. nov., sp. nov. is proposed. The type strain of Limimonas halophila is strain IA16T (= IBRC-M 10018T= DSM 25584T).

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