Pediobius metallicus (Hymenoptera: Eulophidae): First record of a parasitoid wasp of the agromyzid fly Japanagromyza tokunagai, a serious pest of orchids

Agromyzid flies, also known as leafminer flies, are one of the most serious insect pests that infest various plants. An agromyzid fly Japanagromyza tokunagai lays eggs in the ovaries of various Japanese orchids during or shortly after anthesis. Consequently, seed predation by J. tokunagai has the potential to severely limit the reproduction of many endangered orchids in Japan. While agromyzid populations tend to be suppressed by rich communities of natural parasitoids, such parasitoids have yet to be reported. Here we report Pediobius metallicus as the first record of a parasitoid of J. tokunagai. It is highly unusual to find parasitoids infesting J. tokunagai, possibly because the fly is protected by the thick wall and three-dimensional structure of orchid capsule. Possibly due to the thick wall and three-dimensional structure of orchid capsules, parasitoid infesting J. tokunagai seems to be rare. Pediobius metallicus may play an important role in suppressing J. tokunagai population at least in our study site.