The ichneumon wasp (Ichneumon eumerus) is a species of parasitic wasp native to Europe and Asia. It is a predator, and has a similar niche to the North American bald-faced hornet. Its life cycle, however, is different. The ichneumon wasp, as a larva, depends on parisitizing other larvae for its survival, and often kills its host. Ichneumon wasps are often kept in greenhouses to keep pests under control.
Ichneumon wasps are slender, and elegant in design. Their bodies are brightly coloured and often vividly patterned. The color of their ranges from black, beige, and orange to black, white, and red. Unlike related species, Ichneumon eumerus has fairly short antennae, about half the length of the body; in related species the antennae may count for over 2/3 of the wasp's total length. Like all wasps, eumerus have proprtionally large eyes; these allow the wasp not only to have a wider field of vision, but also allows it to look for prey at night. The wings of Ichneumon eumerus are larger than average for ichneumon wasps, and are transparent, lacking the yellowish tinge that other species of ichneumon wasps tend to have on their wings.