Food habit of Platydemus manokwari De Beauchamp, 1962 (Tricladida: Terricola: Rhynchodemidae), known as a predatory flatworm of land snails in the Ogasawara (Bonin) Islands, Japan

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The distribution and food habit of the flatworm species Platydemus manokwari, which is known to be a predator of land snails, were examined on Chichijima Island of the Ogasawara (Bonin) Islands, Japan. P. manokwari was distributed over a wide area of the island. Few live land snails were found in the area where P. manokwari was distributed. Further, it was revealed that P. manokwari fed not only on live land snails including predatory species, but also on other food resources such as live flatworms or a land nemertean species and the carcasses of slugs and earthworms. Therefore, P. manokwari is expected to survive even if the populations of land snails are almost lost on Chichijima Island in the future, and so will affect the biodiversity of Chichijima Island.