Aquimarina rhabdastrellae sp. nov., isolated from the marine sponge Rhabdastrella globostellata

A Gram-stain-negative, aerobic, motile-by-gliding bacterium, designated strain RHTr2 T , was isolated from the marine sponge Rhabdastrella globostellata collected in waters surrounding the Penghu Islands, Taiwan. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain RHTr2 T displayed the highest 16S rRNA gene sequence similarities to Aquimarina versatilis CBA3207 T (94.2%), Aquimarina acroporae D1M17 T (93.7%) and Aquimarina intermedia LMG 23204 T (93.2%). Strain RHTr2 T grew with 1–5% (w/v) NaCl (optimum, 2–3%), at 17–37 °C (optimum, 30 °C) and at pH 6.0–8.0 (optimum, pH 6.0–7.0). Strain RHTr2 T was able to degrade starch, Tweens (20, 40 and 80) and gelatin; flexirubin-type pigments were produced. Strain RHTr2 T contained menaquinone 6 as the major respiratory quinone, and iso-C 15 : 0 and iso-C 17 : 0 3-OH as major fatty acids (> 10%). The polar lipids of strain RHTr2 T were an unidentified aminophospholipid, three aminolipids, a phospholipid and an unidentified polar lipid. The DNA G+C content was 31.4 mol% based on genome sequence analysis. The average nucleotide identity and digital DNA–DNA hybridization values between strain RHTr2 T and the most closely related members of the Aquimarina genus were lower than the recommended thresholds for species delineation. Based on its phenotypic and genotypic characteristics and on the phylogenetic and phylogenomic evidence presented, strain RHTr2 T represents a novel species of the genus Aquimarina for which the name Aquimarina rhabdastrellae sp. nov. is proposed. The type strain is RHTr2 T (=JCM 37598 T =UCCCB 217 T ).