Ten Novel Species Belonging to the Genus Flavobacterium , Isolated from Freshwater Environments: F. praedii sp. nov. , F. marginilacus sp. nov., F. aestivum sp. nov., F. flavigenum sp. nov., F. luteolum sp. nov., F. gelatinilyticum sp. nov., F. aquiphilum sp. nov., F. limnophilum sp. nov., F. lacustre sp. nov., and F. eburneipallidum sp. nov.

Eleven bacterial strains were isolated from freshwater environments and identified as Flavobacterium based on 16S rRNA gene sequence analyses. Complete genome sequences of the 11 strains ranged from 3.45 to 5.83 Mb with G + C contents of 33.41–37.31%. The average nucleotide identity (ANI) values showed that strains IMCC34515 T and IMCC34518 belonged to the same species, while the other nine strains represented each separate species. The ANI values between the strains and their closest Flavobacterium species exhibited ≤ 91.76%, indicating they represent each novel species. All strains had similar characteristics such as being Gram-stain-negative, rod-shaped, and contained iso-C 15:0 as the predominant fatty acid, menaquinone-6 as the respiratory quinone, and phosphatidylethanolamine and aminolipids as major polar lipids. Genomic, phylogenetic, and phenotypic characterization confirmed that the 11 strains were distinct from previously recognized Flavobacterium species. Therefore, Flavobacterium praedii sp. nov. (IMCC34515 T = KACC 22282 T = NBRC 114937 T ), Flavobacterium marginilacus sp. nov. (IMCC34673 T = KACC 22284 T = NBRC 114940 T ), Flavobacterium aestivum sp. nov. (IMCC34774 T = KACC 22285 T = NBRC 114941 T ), Flavobacterium flavigenum sp. nov. (IMCC34775 T = KACC 22286 T = NBRC 114942 T ), Flavobacterium luteolum sp. nov. (IMCC34776 T = KACC 22287 T = NBRC 114943 T ), Flavobacterium gelatinilyticum sp. nov. (IMCC34777 T = KACC 22288 T = NBRC 114944 T ), Flavobacterium aquiphilum sp. nov. (IMCC34779 T = KACC 22289 T = NBRC 114945 T ), Flavobacterium limnophilum sp. nov. (IMCC36791 T = KACC 22290 T = NBRC 114947 T ), Flavobacterium lacustre sp. nov. (IMCC36792 T = KACC 22291 T = NBRC 114948 T ), and Flavobacterium eburneipallidum sp. nov. (IMCC36793 T = KACC 22292 T = NBRC 114949 T ) are proposed as novel species.