Type and non-type specimens of Spirobranchus akitsushima sp. nov. A–E, H, I Kamakura specimens F Hayama specimens B, C mature female specimen A ventral view, lateral band of peduncle (arrows) D, F, G dorsal view B, E lateral view E bilobed wing tip (arrows) F, G operculum in dorsal view, middle constriction (arrows) H, I dissected endplate H lower view, covered with a blue membrane I lateral view. Abbreviations: ac, achaetous chaetiger; ap, apron; c, collar; pd, peduncle; w, wing. Scale bars: 1 mm (A, B); 2 mm (C, D, F, G); 0.5 mm (E, H, I).