A bacterial strain designated FSY-15 T was isolated from a freshwater mesocosm in Taiwan and characterised using a polyphasic taxonomic approach. Cells of strain FSY-15 T were Gram-negative, aerobic, non-spore forming, non-motile rods and formed orange coloured colonies. Growth occurred at 20-30 C (optimum, 25 C), at pH 6-7.5 (optimum, pH 7) and with 0-0.5 % NaCl (optimum, 0 %). Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain FSY-15 T formed a phylogenetic lineage in the the family Cytophagaceae. Strain FSY-15 T was most closely related to the genera Pseudarcicella and Arcicella, and the levels of 16S rRNA gene sequence identity with respect to members of related genera are less than 94.1 %. Strain FSY-15 T showed less than 68.8 % average nucleotide identity and less than 24.7 % digital DNA-DNA hybridisation identity compared to the type strains of related genera within the family Cytophagaceae. The predominant fatty acids were iso-C 15 : 0 , C 16 : 1 !5c and the major hydroxyl fatty acid was iso-C 15 : 0 3-OH. The major isoprenoid quinone was MK-7 and the DNA G+C content was 35.8 mol%. The major polar lipids were phosphatidylethanolamine and several uncharacterised aminophospholipid, aminolipid, phospholipid and lipid. The major polyamine was spermidine. On the basis of the genotypic and phenotypic data, strain FSY-15 T represents a novel species of a new genus in the family Cytophagaceae, for which the name Sandaracinomonas limnophila gen. nov., sp. nov. is proposed.