A Gram-staining-negative, moderately halophilic bacterium, designated strain AN9T, was isolated from a tidal flat of the Taean coast in South Korea. Cells were catalase- and oxidase-positive short rods that were motile by means of a single polar flagellum. Growth of strain AN9T was observed at 15-40 degrees C (optimum, 25-30 degrees C) and at pH 6.0-8.0 (optimum, pH 6.5-7.5). Strain AN9T contained ubiquinone Q-8 as the predominant isoprenoid quinone and C10:0 3-OH (31.7%), C18:1omega7c (24.8%), C16:0 (14.7%) and summed feature 3 (comprising C16:1omega7c and/or iso-C15:0 2-OH, 10.72%) as the major fatty acids. The G+C content of the genomic DNA of strain AN9T was 58 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain AN9T was related to members of the genus Marinobacterium and was related most closely to Marinobacterium litorale IMCC1877T (96.8% similarity). On the basis of chemotaxonomic and molecular data, strain AN9T is considered to represent a novel species of the genus Marinobacterium, for which the name Marinobacterium lutimaris sp. nov. is proposed. The type strain is AN9T (=KACC 13703T =DSM 22012T).