A Gram-negative, non-flagellated, non-spore-forming and rod-shaped bacterial strain, SW-152(T), was isolated from sea water of the Yellow Sea in Korea, and subjected to a polyphasic taxonomic study. Strain SW-152(T) grew optimally at 30 degrees C and in the presence of 2-3% (w/v) NaCl. It contained MK-7 as the predominant menaquinone and iso-C-15:0 and iso-C-15:1 as the major fatty acids. Polar lipids detected in strain SW-152(T) were phosphatidylethanolamine, diphosphatidylglycerol and unidentified lipids. The DNA G + C content was 40.3 mol%. Phylogenetic trees based on 16S rRNA gene sequences exhibited that strain SW-152(T) forms a distinct evolutionary lineage within the Cytophaga-Flavobacterium-Bacteroides (CFB) group. Strain SW-152(T) exhibited low 16S rRNA similarity levels of less than 89-4% to members belonging to the CFB group. Phenotypic properties of strain SW-152(T) differentiate it from phylogenetically related taxa. On the basis of phenotypic and phylogenetic data, strain SW-152(T) (= KCTC 12312(T) = JCM 12600(T)) was classified in a novel genus and species, Marinicola seohaensis gen. nov., sp. nov.