Discovery of a new species of inquiline gall wasp (Hymenoptera: Cynipidae: Diastrophini) in declining greenspace in Tokyo

Periclistus yorikoae Abe and Ide sp. nov. (Hymenoptera: Cynipidae: Diastrophini) was discovered in the urban ecosystem of Tokyo and is described in this article. This new cynipid is an inquiline gall wasp that lives inside galls induced by the Japanese rose gall wasp Diplolepis japonica (Walker) (Hymenoptera: Diplolepididae) on Rosa multiflora Thunb. (Rosaceae). Periclistus yorikoae is typically univoltine, but some individuals spend another year as larvae. This is the first record of prolonged diapause in inquiline gall wasps. The discovery of this new species indicates that the conservation of the remaining greenspaces as strongholds of native creatures in the flatlands of Tokyo, where this new inquiline gall wasp is considered to have been widely distributed before urbanization, is valuable.