Bethylid wasps are a diverse group of parasitic wasps. Though most are solitary, some are social and live in colonies like bees and ants. They range in size from 1 to 5 mm and are often black, brown, or metallic green, with some having brightly colored markings. Bethylid wasps are parasitoids, meaning they lay their eggs on or inside the bodies of other insects, where their larvae hatch and feed on the host’s tissues.
Bethylid wasps can be beneficial because they help to control populations of other insects that can be pests. For example, bethylid wasps are used as biological control agents against cockroaches, flies, and mosquitoes.