Flagellimonas aquimarina sp. nov., and transfer of Spongiibacterium flavum Yoon and Oh 2012 and S. pacificum Gao et al. 2015 to the genus Flagellimonas Bae et al. 2007 as Flagellimonas flava comb. nov. and F. pacifica comb. nov., respectively.

A Gram-stain-negative, non-spore-forming, rod-shaped, aerobic and diffusible yellow-coloured bacterial strain, designated strain ECD12T was isolated from a seaweed, Ecklonia cava. The isolate required sea salts for growth. Catalase-positive and oxidase-negative. A phylogenetic tree based on 16S rRNA gene sequences showed that strain ECD12T formed an evolutionary lineage within the radiation enclosing the members of genera Spongiibacterium and Flagellimonas sharing the highest similarity to Flagellimonas eckloniae DOKDO007T (96.8 % 16S rRNA gene sequence similarity) followed by Spongiibacterium pacificum SW169T (96.4 %) and Spongiibacterium flavum DSM 22638T (96.1 %). The major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH and iso-C15 : 1 G. The new isolate contained MK-6 as the only isoprenoid quinone and phosphatidylethanolamine, two unidentified amino lipids and two unidentified lipids as the major polar lipids. The genomic DNA G+C content is 39 mol%. A number of phenotypic characteristics such as the production of diffusible pigment distinguished strain ECD12T from the related species. On the basis of the evidence presented in this study, a novel species, Flagellimonas aquimarina sp. nov., is proposed for strain ECD12T (=KCTC 52351T=JCM 32292T). Based on the sequence similarity, phylogenetic relationship and common morphological, physiological and chemical characters among the members of the genera Spongiibacterium and Flagellimonas, it is recommended that the two genera are combined into a single genus. Thus, transfer of S. flavumYoon and Oh 2012 and S. pacificum Gao et al. 2015 to the genus FlagellimonasBae et al. 2007 as Flagellimonas flava comb. nov. and Flagellimonas pacifica comb. nov., respectively, is also proposed.