A Gram-staining-negative, non-flagellated, non-gliding and pleomorphic bacterial strain, designated DPG-25(T), was isolated from seawater in a seaweed farm in the South Sea in Korea and its taxonomic position was investigated by using a polyphasic approach. Strain DPG-25(T) grew optimally at 25 degrees C, at pH 7.0-7.5 and in the presence of 2% (w/v) NaCl. Flexirubin-type pigments were not produced. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain DPG-25(T) formed a cluster with the type strains of Actibacter sediminis, Aestuariicola saemankumensis and Lutimonas vermicola. Strain DPG-25(T) exhibited 16S rRNA gene sequence similarity values of 95.3, 93.1 and 93.6% to the type strains of Actibacter sediminis, Aestuariicola saemankumensis and L. vermicola, respectively. Strain DPG-25(T) contained MK-6 as the predominant menaquinone and iso-C-15:0 and iso-C-17:0 3-OH as the major fatty acids. The major polar lipids detected in strain DPG-25(T) were phosphatidylethanolamine and one unidentified lipid. The DNA G+C content was 39.9 mol%. Differential phenotypic properties and the phylogenetic distinctiveness of strain DPG-25(T) demonstrated that this strain is distinguishable from Actibacter sediminis, Aestuariicola saemankumensis and L. vermicola. On the basis of the data presented here, strain DPG-25(T) represents a novel species in a novel genus of the family Flavobacteriaceae, for which the name Namhaeicola litoreus gen. nov., sp. nov. is proposed. The type strain of Namhaeicola litoreus is DPG-25(T) (=KCTC 23702(T) =CCUG 61485(T)).