Discovery of the genus Formosiepyris Terayama, (Hymenoptera, Bethylidae) in Vietnam, with a description of a new species.

Formosiepyrisvietnamensis sp. n. (Hymenoptera: Bethylidae) is described based on material collected from Da Lat, southern Vietnam. This is the first record of Formosiepyris Terayama from Vietnam. The new species can be distinguished from other Formosiepyris species by a narrow and rounded clypeus; a mandible with three teeth; a second metasomal tergite having small, sparsely distributed punctures and smooth interspaces, except for anterior 2/5, which is microreticulate; and a head length : width aspect ratio of 10 : 11. A key to the Oriental species of Formosiepyris is provided.