A Gram-stain-negative, rod-shaped, orange-coloured, catalase- and oxidase-positive, non-motile bacterium, designated strain 92V(T), was isolated from the marine sponge Amphilectus fucorum, collected from Lough Hyne, County Cork, Ireland. 16S rRNA gene sequence analysis revealed that strain 92V(T) clustered with members of the family Flavobacteriaceae, the closest member being Aquimarina latercula NCIMB 1399(T), with a gene sequence similarity of 97.5%. Strain 92V(T) required seawater for growth with optimal growth occurring at 25 °C, at pH 6-7 and with 3% (w/v) NaCl. MK-6 was the sole respiratory quinone present and the major fatty acids were iso-C(17 : 0) 3-OH, iso-C(15 : 0), iso-C(17 : 1)ω9c and iso-C(15 : 0) 3-OH. The DNA G+C content was 36.1 mol%. Combined phenotypic differences and phylogenetic analysis indicate that strain 92V(T) represents a novel species of the genus Aquimarina, for which the name Aquimarina amphilecti sp. nov. is proposed. The type strain is 92V(T) ( = NCIMB 14723(T) = DSM 25232(T)).