A Gram-stain-negative, non-motile, rod-shaped, red-pigmented, facultatively anaerobic bacterium, designated SS2-9^T, was isolated from sediment collected from a sea cucumber culture pond located in Rongcheng, Shandong province, China. Cells of strain SS2-9^T were approximately 0.3–0.5 µm in width and 1.5–6.0 µm in length. The strain was able to grow at 10–37 °C, at pH 6.5–8.5 and in the presence of 0.5–6.0 % (w/v) NaCl. It grew optimally at 28 °C and in the presence of 2.0 % (w/v) NaCl. The DNA G+C content was 34.5 mol% and the sole respiratory quinone was menaquinone 6 (MK-6). The predominant cellular fatty acids were C_15 : 0, iso-C_15 : 1 G, iso-C_15 : 0 and iso-C_17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, an unidentified phospholipid, two unidentified aminolipids and four unidentified lipids. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain SS2-9^T was phylogenetically related to members of the genus Aquimarina and was closely related to Aquimarina amphilecti 92V^T (97.29 % similarity). On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain SS2-9^T was considered to represent a novel species of the genus Aquimarina, for which the name Aquimarina rubra sp. nov. is proposed. The type strain is SS2-9^T (=KCTC 52274^T=MCCC 1H00142^T).