Systasidae is a family of chalcidoid wasps found worldwide. Members of the family are parasitoid, mostly parasitizing the gall-forming flies Agromyzidae and Cecidomyiidae, however hosts from other orders such as Coleoptera and Lepidoptera have been recorded.
Small (body length 0.6âÂÂ3.0 mm) dark, bronze or metallic green wasps. They have a very unusual mesofurcal pit placement, which is placed between mesocoxal insertions.
The genera currently included in the family were originally placed under Pteromalidae. In 2022, the family was described based on an analysis of a combination of molecular, morphological, and life history data. Systasidae contains the following subfamilies and genera with a total of 81 species: