A Gram-stain-negative, aerobic, non-flagellated, and coccoid, ovoid or rod-shaped bacterium, designated JDTF-65(T), was isolated from a tidal flat on the south-western sea in Republic of Korea. Strain JDTF-65(T) grew optimally at 25 degrees C, at pH 7.0-8.0 and in the presence of 2.0% (w/v) NaCl. Strain JDTF-65(T) exhibited 16S rRNA gene sequence similarities of 97.1-97.6% to the type strains of 'Aliisedimentitalea scapharcae', Phaeobacter gallaeciensis, Phaeobacter inhibens, Leisingera aquimarina, Tropicibacter litoreus, Sulfitobacter pseudonitzschiae, and Pseudoseohaeicola caenipelagi. Phylogenetic trees based on 16S rRNA gene sequences showed that strain JDTF-65(T) forms an independent lineage within the radiation enclosed by the family Rhodobacteraceae. Strain JDTF-65(T) contained Q-10 as the predominant ubiquinone and C-18:1 omega 7c as the major fatty acid. The major polar lipids of strain JDTF-65(T) were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminolipid, and one unidentified lipid. The DNA G+C content of strain JDTF-65(T) was 56.8 mol% and its DNA-DNA relatedness values with the type strains of the phylogenetically related species were 13-27%. Differential phenotypic properties revealed that strain JDTF-65(T) is separated from representatives of some phylogenetically related taxa. On the basis of the data presented, strain JDTF-65(T) represents a new genus and species within the family Rhodobacteraceae, for which the name Jindonia aestuariivivens gen. nov., sp. nov. is proposed. The type strain of Jindonia aestuariivivens is JDTF-65(T) (=KCTC 52564(T) =NBRC 112534(T)).