Fluctibacter corallii gen. nov., sp. nov., isolated from the coral Montipora capitata on a reef in Kāne'ohe Bay, O'ahu, Hawai'i, reclassification of Aestuariibacter halophilus as Fluctibacter halophilus comb. nov., and Paraglaciecola oceanifecundans as a later heterotypic synonym of Paraglaciecola agarilytica.

Strain AA17 was isolated from an apparently healthy fragment of Montipora capitata coral from the reef surrounding Moku o Lo'e in Kāne'ohe Bay, O'ahu, Hawai'i, USA, and was taxonomically evaluated using a polyphasic approach. Comparison of a partial 16S rRNA gene sequence found that strain AA17 shared the greatest similarity with Aestuariibacter halophilus JC2043 (96.6%), and phylogenies based on 16S rRNA gene sequences grouped strain AA17 with members of the Aliiglaciecola, Aestuariibacter, Lacimicrobium, Marisediminitalea, Planctobacterium, and Saliniradius genera. To more precisely infer the taxonomy of strain AA17, a phylogenomic analysis was conducted and indicated that strain AA17 formed a monophyletic clade with A. halophilus JC2043, divergent from Aestuariibacter salexigens JC2042 and other related genera. As a result of monophyly and multiple genomic metrics of genus demarcation, strain AA17 and A. halophilus JC2043 comprise a distinct genus for which the name Fluctibacter gen. nov. is proposed. Based on a polyphasic characterisation and identifying differences in genomic and taxonomic data, strain AA17 represents a novel species, for which the name Fluctibacter corallii sp. nov. is proposed. The type strain is AA17 (= LMG 32603 = NCTC 14664). This work also supports the reclassification of A. halophilus as Fluctibacter halophilus comb. nov., which is the type species of the Fluctibacter genus. Genomic analyses also support the reclassification of Paraglaciecola oceanifecundans as a later heterotypic synonym of Paraglaciecola agarilytica.