A Gram-staining-negative, cream pigmented, motile, extremely halophilic archaeon, designated strain IC38T, was isolated from a saline mud sample of the hypersaline lake Aran-Bidgol in Iran. The strain required at least 2.5 NaCl M for growth. However, MgCl2 is not required. Optimal growth was achieved at 4.3 M NaCl and 0.2 M MgCl2. The optimum pH and temperature for growth were pH 7.0 and 35 °C, respectively, and it was able to grow over a pH range of 6.5 to 9.0, and a temperature range of 25 to 45 °C. Analysis of 16S rRNA gene sequence revealed that strain IC38T clustered with the two species of the genus Halovivax, Halovivax asiaticus EJ-46T and Halovivax ruber XH-70T, with a sequence similarity of 96.4% and 96.1%, respectively. The rpoB′ gene similarity between novel strain and Halovivax asiaticus and Halovivax ruber were 90.7 % and 90.3 %, respectively. The polar lipid pattern of strain IC38T consisted of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. Three unidentified glycolipids and two minor phospholipids were also observed. The G+C content of its DNA was 62.6 mol%. On the basis of the phylogenetic analysis as well as biochemical and physiological characteristics, the new isolate could be classified as a novel species of the genus Halovivax, for which the name Halovivax limisalsi sp. nov. is proposed. The type strain of Halovivax limisalsi is IC38T (=IBRC-M 10022T = KCTC 4051T).

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