A novel red-pigmented halophilic archaeon, strain EB27T, was isolated from Aran-Bidgol salt lake, a hypersaline playa in Iran. The cells of strain EB27T were nonmotile and pleomorphic, from rods to triangular or disk shaped. Strain EB27T needs at least 2.5 M NaCl and 0.1 M MgCl2 for growth. Optimal growth was achieved at 4 M NaCl and 0.5 M MgCl2. The optimum pH and temperature for growth were pH 7.5 and 40 °C, respectively, while it was able to grow over a pH range and a temperature range of 6.0-8.0 and 25-50 °C, respectively. Analysis of the 16S rRNA gene sequence showed that strain EB27T is a member of the family Halobacteriaceae; however, its similarity was as low as 90.0 %, 89.3 % and 89.1 % to the most closely related haloarchaeal taxa including Halalkalicoccus, Halosimplex and Halorhabdus type species, respectively. The G+C content of its DNA is 61 mol%. Phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester, common phospholipids found in haloarchaea, were present. Two minor phospholipids were also observed. The only quinone present was MK-8(ΙΙ-H2). The physiological, biochemical and phylogenetic differences between strain EB27T and other previously described genera of extremely halophilic archaea suggest that this strain represents a novel species in a new genus within the family Halobacteriaceae, for which the name Halovenus aranensis gen. nov., sp. nov. is proposed. The type strain of Halovenus aranensis is strain EB27T (= IBRC 10015T= CGMCC 1.11001T).

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