A novel Gram-staining-negative, rod-shaped, non-motile bacterium, strain AMV16T, was isolated from a soil sample collected from a mud volcano located in the Andaman Islands, India. The cell suspension was pale orange. Cells of strain AMV16T were positive for catalase, oxidase, lipase, ornithine decarboxylase and lysine decarboxylase and negative for gelatinase and urease. The fatty acids present were anteiso-C11 : 0 (5.4 %), anteiso-C12 : 0 (4.1 %), C12 : 0 (7.0 %), iso-C15 : 0 (14.4 %), anteiso-C15 : 0 (3.4 %), anteiso-C16 : 0 (3.0 %), C16 : 0 (2.6 %), anteiso-C17 : 0 (3.7 %), iso-C19 : 0 (9.7 %), C13 : 1 (13.8 %), iso-C15 : 1 G (15.9 %), iso-C16 : 1 G (11.1 %) and summed feature 5 (anteiso-C18 : 0 and/or C18 : 2ω6,9c; 5.9 %). Strain AMV16T contained MK-4 as the major respiratory quinone and diphosphatidylglycerol and phosphatidylethanolamine made up the phospholipids. The G+C content of DNA of strain AMV16T was 50.9 mol%. blast sequence similarity searches based on the 16S rRNA gene sequence indicated that species of the genus Marivirga were the nearest phylogenetic neighbours, with pairwise sequence similarity ranging from 89.9 to 90.0 %. Phylogenetic analyses indicated that strain AMV16T clustered with the type strains of Marivirga tractuosa and Marivirga sericea at a phylogenetic distance of 14.6 % (85.4 % similarity), distinct from clades representing other genera of the family ‘Flammeovirgaceae’. Based on the above-mentioned phenotypic and phylogenetic characteristics, strain AMV16T is proposed as a representative of a new genus and novel species, Cesiribacter andamanensis gen. nov., sp. nov. The type strain of Cesiribacter andamanensis is AMV16T ( = DSM 22818T = CCUG 58431T).