Jesogammarus uchiyamaryui sp. n., holotype, male (10.3 mm), NSMT-Cr 25474. A–C dorsal margins of pleonites 1–3, respectively, dorsal views; D–F epimeral plates 1–3, respectively, lateral views; G–I dorsal margins of urosomites 1–3, respectively, dorsal views; J peduncular articles 1–3, accessory flagellum, and flagellar articles 1–3 of antenna 1, medial view; K peduncular articles 1–5 and flagellar articles 1–3 of antenna 2, medial view; L calceolus of antenna 2, medial view; M upper lip, anterior view; N left mandible, medial view; O incisor and lacinia mobilis of left mandible, lateral view; P incisor and lacinia mobilis of right mandible, lateral view; Q lower lip, ventral view.