A wasp, 3–40 mm long, variable in colour, with many being yellow, brown, or black, and others having bright yellow and black or black and brown patterning. It has a long ovipositor with which it may make stinging movements if handled, although it will not sting. Ichneumons are parasites, each subfamily or tribe specializing in a particular group of insects, their larvae or pupae, and many are important in biological control. There are more than 60,000 species (family Ichneumonidae) found worldwide.