Minami-Daito is an oceanic island located about 360 km east of Okinawa Island (a continental island), Ryukyu Archipelago, Japan. This is the first report of a peltogastrid rhizocephalan from an oceanic island in the northern hemisphere. The present specimen was identified as Dipterosaccus indicus based on the diagnostic characters of its external and internal morphology. Molecular analyses based on the partial sequence of the COI gene were consistent with the morphological identification. The number of species reported from oceanic islands may be limited by the lack of diversity in the structure and condition of their coastline, as well as the dispersal abilities of peltogastrids and their hosts.
