Variation of Nereis species studied. N. oligohalina A, D, J–L, O, Q from ECOSUR–OH–P0760. N. garwoodi B, E from paralectotype ECOSUR 0066; I, M, R from ECOSUR P2834. N. confusa sp. n. C, F–H, N, P from ECOSUR P2838. A–C Pharynges everted, dorsal view D–F Pharynges everted, ventral view G Pharynx everted, anterior view, showing merged paragnaths (arrows) H Close-up of merged paragnaths on area IV I–J Variations on area I K Variations on areas V and VI L Fingerprint-like pattern, dorsal view M–N Pigmentation patterns on anterior ends, dorsal view O Parapodial furrow in posterior end, lateral view (arrow indicates start) P Specimen on tube, dorsal view Q Parapodium from posterior chaetiger, anterior view R Ventral cirrus duplicated, chaetiger 5, anterior view. Scale bars: 0.5 mm (A–F, L); 1 mm (M–P); 0.1 mm (Q–R).