As a member of the wasp group, the ichneumon must have been the inspirational bad-girl of Ridley Scott's movie, Alien . As a zoology student's introduction to parasitism, it was hard for me not to view the ichneumon as a study in good vs. evil, the vanquished and the villain. The ichneumon, like the Alien, implants its egg into a living host. They both have tube-like ovipositors. The egg is deposited into the body of the victim.
Biologists call it endoparasitism , when the invader dwells within.
For the ichneumon , its host is usually a caterpillar. With eggs safely injected, the female leaves. Like the doomed crew of the starship Nostromos with its alien predator lurking in the air ducts, death is now inevitable. When newly hatched, the parasites start to eat. The caterpillar starts to twitch.