Chalcididae is a family of parasitic wasps that includes over 2,300 species. Some synonyms for Chalcididae include chalcids, chalcid flies, and chalcid wasps. These insects are known for their small size, typically ranging from 1 to 10 millimeters in length, and the diversity of their habitats. They are found in almost every region of the world, from tropical rainforests to deserts, and they can be important biological control agents of pest insects. Chalcididae are easily recognized by their characteristic antennal structures, which are often divided into many segments and have a distinctive "elbow" shape.