• Utica gracilipes Nise-mokuzugani
  
• Utinomiella dimorpha Utinomi-sango-yadori
  
• Vargula norvegica
• Varuna litterata Oh-hiraisogani
  
• Varuna yui Paddler crab
  Yu-óh-hiraisogani
  
• Vaunthompsonia cristata
• Velella velella
• Vellodius etisoides Kebuka-tenaga-ohgi
  
• Viaderiana quadrispinosa Hime-okinagani
  
• Viaderiana typica Ward-okinagani
  
• Vogtia spinosa
• Websterinereis glauca
• Xanthasia murigera Heso-pinno
  
• Xanthias canaliculatus Mizo-himeohgigani
  
• Xanthias cherbonnieri Guinot-himeohgigani
  
• Xanthias elegans Himeohgigani
  
• Xanthias gilbertensis Gilbert-himeohgigani
  
• Xanthias lamarcki Lamarck-himeohgigani
  
• Xanthias latifrons Kobu-himeohgigani
  
• Xanthias lividus Murasaki-himeohgigani
  
• Xanthias maculatus Rurimon-gani
  
• Xanthias punctatus Mauritius-himeohgigani
  
• Xanthias tetraodon Heller-himeohgigani
  
• Xeinostoma sakaii Maru-mameheike-gani
  
• Xenocarcinus conicus Nakazawa-ísobana-gani
  
• Xenocarcinus depressus Isobana-gani
  
• Xenocarcinus monoceros Itsukaku-ísobana-gani
  
• Xenocarcinus tuberculatus Ibo-ísobana-gani
  
• Xenograpsus novaeinsularis Mariana-íwagani
  
• Xenophthalmodes morsei Morusu-gani
  
• Xenophthalmus pinnotheroides Menashi-pinno
  
• Xynomaia boissoni Nhatrang-sango-yadori
  
• Yaldwynopsis spinimanus Hari-homora
  
• Zalasius dromiaeformis Doroishi-gani
  
• Zalasius horii Marumi-doroishi-gani
  
• Zalasius imajimai Tsubu-doroishi-gani
  
• Zalasius sakaii Tune-doroishi-gani
  
• Zanclea costata
• Zebrida adamsi Zeburagani
  
• Zehntneria amakusae Amakusa-kushiha-gani
  
• Zehntneria miyakei Sadayoshi-kushiha-gani
  
• Zehntneria novaeinsulicola Niijima-kushiha-gani
  
• Zehntneria villosa Biroudo-zehntner-gani
  
• Zosimus aeneus Umore-ohgigani
  
• Zozymodes cavipes Eriashi-ohgigani
  
• Zozymodes pumilus Guam-ériashi-ohgigani