Cotesia species

Cotesia is a genus of parasitoids that use caterpillars as their host. Below some examples of this diverse genus.

The parasitoid wasp Cotesia glomerata inserts her ovipositor in one of a cluster of first instar caterpillars of the large cabbage white, Pieris brassicae. The caterpillars bite and spit their toxic regurgitant on the wasp, which temporarily paralyzes the wasp and gives some of the caterpillars time to escape. This wasp is covered with regurgitant on her eye. The parasitized caterpillars have some 20 eggs of the wasp inside, which will develop until the caterpillar reaches the last instar, when the fully grown wasp larvae escape from their host (see picture in gallery below). The caterpillar will then die. Below some more pictures of the genus Cotesia
Movie (4k video) of the larval endoparasitoid wasp Cotesia glomerata. She attacks the caterpillars of the Large white butterfly, Pieris brassicae. She inserts her ovipositor in the body of the caterpillars and quickly lays some 20-30 eggs. The caterpillars spit and bite the wasp to defend themselves, but many will have the parasitoid’s eggs inside, which will soon develop into larvae. Both the caterpillars and the parasitoid larvae continue to grow untill both are fully developed. You can see the maggot like larvae in a part of the movie where the skin of the caterpillar has been made transparent. Just before the caterpillar would normally moult into a pupa, the parasitoid larvae eat themselves through the skin and start spinning a cocoon in which they will continue their development to pupa and adult wasp. The caterpillar still lives, but it’s behaviour is manipulated. It will protect the parasitoid wasps from attackers, such as hyperparasitoids, and spins a protective layer of silk over the cluster of cocoons. After some days it will die because it’s energy reserves have been fully exploited by the developing parasitoid larva. Then the adult wasps emerge from their cocoons to mate and start a new cycle