Nasonia vitripennis is a small parasitoid wasp (about 2 mm), which lays eggs inside different species of fly pupas. The feeding activity of Nasonia larvae blocks immediately the host growth and they can reach quickly the adult stage. In this way, new individuals of the parasitoid will come out from parasitized pupas, and will start to search for other hosts.
The life cycle is very fast (about 2 weeks at 25 °C) and goes through 3 larval stages plus one pupal stage, all within the host before the emergence of the adult. Each female may lay over 300 eggs during its lifetime that can last approximately up to 15 days.
Nasonia vitripennis is a gregarious parasitoid. This means that several eggs are laid in one single fly pupa. In this way, from each parasitized host, an average of more than 9 adults may develop. Thanks to the combination of high fecundity and fast development, if not disturbed by negative factors or bad manure management the population can grow rapidly and colonize the area of release.