Parasitica
The term parasitoid wasp refers to a large evolutionary grade of hymenopteran superfamilies, mainly in the Apocrita. The parasitic or parasitoid Apocrita are divided into some dozens of families. They are parasitoids of various animals, mainly other arthropods.
Many of them are considered beneficial to humans because they control populations of agricultural pests. A few are unwelcome because they attack other benefical insects.
Parasitoid wasps range from some of the smallest species of insects, to wasps about an inch long. Most females have a 'spine-like' ovipositor at the tip of the abdomen, sometimes lacking venom glands and almost never modified into a stinger. The egg and larval stage are usually not observed unless dissected from the host, except in species that practically fill the skin of the host with parasitoid larvae.
Listed are Hymenopteran families where most members have a parasitoid lifestyle. All except the Orussidae are in the Apocrita.
Orussoidea (parasitoid wood wasps) 
Apocrita (wasps (parasitoid or not), ants, bees) .jpg){kind=small}
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