The Lampropidae (Crustacea: Cumacea) of the World Author Gerken, Sarah text Zootaxa 2018 2018-06-01 4428 1 1 192 journal article 22652 10.11646/zootaxa.4428.1.1 e10e53f2-0e1b-46f6-8b0f-af19d5529711 1175-5326 3769771 2419A7F0-5AED-47EC-86BB-06AADB2A4BD9 Platysympus japonicus Gamô, 1975 Platysympus japonicus Gamô, 1975: 229–235 , figs 1–2. Type material. Holotype : NSMT , adult female. Sagami Bay , Japan , 34°44.8’N , 139°8.5’E . Not seen. Diagnosis . Carapace with branchial swellings, with 1 pair ridges, in lateral view with single dorsal hump at posterior margin. Telson 2.1 pleonite 6, 0.5 uropod peduncles, without lateral setae. Adult male unknown. Depth . 480 m . Distribution . Sagami Bay, Japan , 34°44.8’N , 139°8.5’E . Remarks . The most similar species are Platysympus typicus and P. depressus . In P. depressus and P. typicus the telson is longer than 0.5 the uropod peduncle length, while in P. japonicus the telson is less than 0.5 uropod peduncle length.