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  3. Platydemus manokwari

Platydemus manokwari

Basic information
Scientific name Platydemus manokwari

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Common names Flatworm
Higher taxon Rhynchodemidae, Tricladida, Turbellaria, Platyhelminthes
Natural range New Guinea
Habitat Forest to grassland in warm area.
Invasion information
Range in Japan Ryukyu Archipelago (Okinawajima, Kumejima, Miyakojima, Irabujima, Ikejima, Henzajima Is.) and Ogasawara Islands (Chichijima Is.) Range in Japan
Origin Unknown for Okinawa populations. From Okinawajima Is. to Ogasawara.
Date The first record in Japan was in October 1990, at southern Okinawajima Island.
Route Accidental: Possibly hitchhiking on transportation of plants.
Impact Predation on ground and arboreal land snails. An intermediate host of angiostrongyliasis (a parasitic disease by Angiostrongylus cantonensis).
Native organism(s) affected: Native land snails (predation). Human (angiostrongyliasis).
Regulation in Japan Import, transport and keeping are prohibited by the Invasive Alien Species Act.
Introduced range in other countries Australia, Guam, Hawaii, Micronesia, Philippines, and other Pacific Islands, and Indian Ocean Islands such as Maldives.
Reference Notes
  • DECO (ed) (2006) Dictionary of Alien Species. Tokyo-Shoseki, Tokyo (in Jpn)
  • Ecol Soc Japan (ed) (2002) Handbook of Alien Species in Japan. Chijin-Shokan, Tokyo. (in Jpn)
  • JWRC (ed) (2008) A Photographic Guide to the Invasive Alien Species in Japan. Heibonsha, Tokyo (in Jpn)
  • Ohbayashi et al. (2005) Food habit of Platydemus manokwari De Beauchamp, 1962 (Trichladida: Terricola: Rhynchodemidae), known as a predatory flatworm of land snails in thet Ogasawara (Bonin) Islands, Japan. Appl Entomol Zool. 40(4), 609-614.
  • Sugiura & Okochi (2006) High predeation pressure by an introduced flatworm on land snails on the oceanic Ogasawara Islands. Biotropica. 38(5), 700-703.
  • Chiba (2010) Species diversity and conservation of Mandarina, an endemic land snail of the Ogasawara Islands. in: Restoring the oceanic island ecosystem. Springer, Tokyo. pp.117-125
  • etc.
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