Ryukyu Islands - Island Subgrouping

Island Subgrouping

The Ryukyus are commonly divided into two or three primary groups:

• either administratively, with the Northern Ryukyus being the islands in Kagoshima Prefecture (known in Japanese as the "Satsunan Islands") and the Southern Ryukyus being the islands in Okinawa Prefecture (known in Japanese as the "Ryukyu Islands"),
• or geologically, with the islands north of the Tokara Strait (Ōsumi and Tokara) being the Northern Ryukyus, those between the Tokara Strait and Kerama Gap (Amami and Okinawa) being the Central Ryukyus, and those south of the Kerama Gap (Miyako and Yaeyama) being the Southern Ryukyus.

Following are the grouping and names used by the Hydrographic and Oceanographic Department of the Japan Coast Guard. The islands are listed from north to south where possible.

• Nansei Islands (南西諸島, Nansei-shotō?)
  • Satsunan Islands (薩南諸島, Satsunan-shotō?)
    • Ōsumi Islands (大隅諸島, Ōsumi-shotō?) with:
      • Tanegashima, Yaku, Kuchinoerabu, Mageshima in the North-Eastern Group,
      • Takeshima, Iojima, Kuroshima in the North-Western Group.
    • Tokara Islands (吐噶喇列島, Tokara-rettō?): Kuchinoshima, Nakanoshima, Gajajima, Suwanosejima, Akusekijima, Tairajima, Kodakarajima, Takarajima
    • Amami Islands (奄美群島, Amami-guntō?): Amami Ōshima, Kikaijima, Kakeromajima, Yoroshima, Ukeshima, Tokunoshima, Okinoerabujima, Yoronjima
  • Ryukyu Islands (琉球諸島, Ryūkyū-shotō?)
    • Okinawa Islands (沖縄諸島, Okinawa-shotō?): Okinawa Island, Kume, Iheya, Izena, Aguni, Ie (Iejima), Iwo Tori Shima (Iōtorishima)
      • Kerama Islands (慶良間諸島, Kerama-shotō?): Tokashiki, Zamami, Aka, Geruma
    • Sakishima Islands (先島諸島, Sakishima-shotō?, the "Further Isles")
      • Miyako Islands (宮古列島, Miyako-rettō?): Miyakojima, Ikema, Ōgami, Irabu, Shimoji, Kurima, Minna, Tarama
      • Yaeyama Islands (八重山列島, Yaeyama-rettō?): Iriomote, Ishigaki, Taketomi, Kohama, Kuroshima, Aragusuku, Hatoma, Yubujima, Hateruma, Yonaguni
      • Senkaku Islands (尖閣諸島, Senkaku-shotō?, claimed by China and Taiwan): Uotsurijima, Kuba Jima, Taisho Jima, Kita Kojima, Minami Kojima
  • Daitō Islands (大東諸島, Daitō-shotō?): Kita Daitō, Minami Daitō, Oki Daitō

The Geospatial Information Authority of Japan, another government organization that is responsible for standardization of place names, disagrees with the Japan Coast Guard over some names and their extent, but the two are working on standardization. They agreed on February 15, 2010, to use Amami-guntō (奄美群島?) for the Amami Islands; prior to that, Amami-shotō (奄美諸島?) had also been used.