Alleurythoe tenuichaeta gen. n. & sp. n., holotype. a Anterior chaetigers, dorsal view b Anterior chaetigers, ventral view c Parapodia of middle chaetiger, posterior view d Greatly reduced harpoon chaeta, notopodium of chaetiger 5 e–g Reduced harpoon chaeta, notopodium of chaetiger 14 h Harpoon chaeta, notopodium of chaetiger 106 i Acicula, notopodium of chaetiger 106 j Capillary chaeta, neuropodium of chaetiger 85 k Bifurcate chaeta, neuropodium of chaetiger 22 l–m Bifurcate chaetae, neuropodium of chaetiger 85 n Simple chaeta, neuropodium of chaetiger 85. Scale bars: a–b 1 mm; c 0.5 mm; d–n 50 μm.