Rhynchospio aciliata sp. nov. A, G holotype (NIBRIV0000893855) B–F, H, I paratype (NIBRIV0000893854) A anterior end, dorsal view B–F parapodium from chaetiger 5, 19, 23, 35, 49, all anterior views G posterior end, left four dorsal cirri removed, lateral view H ventral sabre chaeta of chaetiger 31 I neuropodial hooded hook of chaetiger 31. Scale bars: 0.2 mm (A–F); 0.1 mm (G); 20 μm (H, I).