Aphalara itadori

Aphalara itadori, the Japanese knotweed psyllid, is a species of psyllid from Japan which feeds on Japanese knotweed (Reynoutria japonica). It has been licensed by the UK Government for the biological control of Japanese knotweed in England; this is the first time that biological control of a weed has been sanctioned in the European Union. The specific name comes from itadori (虎杖, イタドリ), the Japanese name for Japanese knotweed. Aphalara itadori Shinji, is a species of psyllid that specializes in feeding on Reynoutria japonica (Japanese knotweed), as well as other Fallopia spp. / Polygonum cuspidatum, such as Reynoutria sachalinensis / Polygonum sachalinense (Giant knotweed) and Reynoutria x bohemica / Polygonum x bohemicum (Himalayan knotweed - the hybrid of giant and Japanese knotweed). Knotweed species' native home range is Asia. They were introduced to North America and Europe in the 1800s. Knotweed was carried from Asia to be used as an ornamental. Since these introductions knotweed species have spread throughout North America, Canada and Europe to establish themselves as a noxious weed. Presently, 180 species of arthropod exist that exhibit a predatorial behavior to Fallopia spp.. Fallopia spp. are species of concern due to their aggressive nature and destruction they cause to natural environments. Specifically, knotweed species have been seen to disrupt riparian habitats and lead to the degradation of waterways they invade. Currently, Aphalara itadori is the only arthropod that has been extensively studied and proven to possess qualities needed in an effective biological control agent for the control of invasive knotweed species. Which is why it has been approved for release in the European Union. A four-year study in England and Wales found that the insects limited the growth of knotweed and did not breed successfully on ninety nearby native species, including the related species rhubarb, although it wasn't clear whether the insect colonies would be able to survive over the winter. The southern strain of Aphalara itadori is from Kyushu and is the strain released in the UK. Its home range is the Kumamoto prefecture, of the Kyushu Island, in Southern Japan. The southern strain attacks Japanese and Bohemian knotweed.