Jesogammarus (Jesogammarus) ikiensis sp. n., holotype, male, 13.1 mm, NSMT-Cr 24107, Ishida, Iki, Nagasaki Prefecture, Japan. A coxa–merus of pereopod 6, lateral view B carpus–dactylus of pereopod 6, lateral view C coxal gill of pereopod 6, lateral view D coxa–merus of pereopod 6, lateral view E carpus–dactylus of pereopod 6, lateral view F coxal gill of pereopod 7, lateral view G pleopod 1, medial view, distal parts of rami omitted H retinacula on peduncle of pleopod 1, medial view I bifid plumose seta (clothes-pin seta) on inner basal margin of inner ramus of pleopod 1, medial view J uropod 1, dorsal view K uropod 2, dorsal view.