Upon encountering a suitable pupal host the "Nasonia" female uses her ovipositor (stinger) to drill a small hole through its chitinous outer puparium. She then commences to inject venom into the host before laying 20 to 40 small eggs on the hosts outer integument. After approximately 36 hours the eggs hatch and the small "Nasonia" larvae use their mandibles to feed on the host. Though the "Nasonia" young develop inside of the host's puparium, as they do not directly enter the body of their prey they are considered ectoparasites.