A new halophilic sulfate-reducing bacterium, strain GSL-But2T, was isolated from surface sediment of the Southern arm of the Great Salt Lake, UT, USA. The organism grew with a number of straight-chain fatty acids (C4-C16), 2-methylbutyrate, L-alanine and pyruvate as electron donors. Butyrate was oxidized incompletely to acetate. Sulfate, but not sulfite or thiosulfate, served as an electron acceptor. Growth was observed between 2 and 19% (w/v) NaCl with an optimum at 4-5% (w/v) NaCl. The optimal temperature and pH for growth were around 34 degrees C and pH 6.5-7.3, respectively. The generation time under optimal conditions in defined medium was around 28 h, compared to 20 h in complex medium containing yeast extract. The G+C content was 35.0 mol%. 16S rRNA gene sequence analysis revealed that strain GSL-But2T belongs to the family Desulfobacteriaceae within the delta-subclass of the Proteobacteria and suggested that strain GSL-But2T represents a member of a new genus. The name Desulfocella halophila gen. nov., sp. nov. is proposed for this organism. The type strain of D. halophila is strain GSL-But2T (= DSM 11763T = ATCC 700426T).