The superfamily Chrysidoidea is a very large cosmopolitan group (some 6,000 described species, and many more undescribed) , all of which are

parasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...

s or

cleptoparasite Kleptoparasitism (etymologically, parasitism by theft) is a form of feeding in which one animal deliberately takes food from another. The strategy is evolutionarily stable when stealing is less costly than direct feeding, which can mean when foo ...

s of other insects. There are three large, common families (

Bethylidae The Bethylidae are a family of aculeate wasps in the superfamily Chrysidoidea. As a family, their biology ranges between parasitoid wasps and hunting wasps. Overview Like most of the Chrysidoidea, the Bethylidae are stinging Hymenoptera and mo ...

Chrysididae Commonly known as cuckoo wasps or emerald wasps, the hymenopteran family Chrysididae is a very large cosmopolitan group (over 3000 described species) of parasitoid or kleptoparasitic wasps, often highly sculptured, with brilliant metallic color ...

, and

Dryinidae Dryinidae is a cosmopolitan family of solitary wasps. Its name comes from the Greek ''drys'' for oak: Latreille named the type genus ''Dryinus'' because the first species was collected in an oak plant in Spain. The larvae are parasitoids of the ...

) and four small, rare families (

Embolemidae Embolemidae is a family of small solitary parasitoid wasps with around 70 species in 2 genera distributed around the world.van Achterberg, Cornelis & Kats, R.. (2000). Revision of the Palaearctic Embolemidae (Hymenoptera). Zoöl. Med. 74 (2000), ...

, Plumariidae,

Sclerogibbidae The Sclerogibbidae are a small family of aculeate wasps in the superfamily Chrysidoidea. Overview Sclerogibbidae are ectoparasitoids of Embioptera. The female wasp oviposits an egg on the abdomen of a host. Once the larva emerges, it attaches ...

, and

Scolebythidae The Scolebythidae are a small family of aculeate wasps in the superfamily Chrysidoidea. These chrysidoid wasps are found in Africa, Australia, the Neotropics, north China, Thailand and Fiji. They are parasites on larvae of Cerambycidae and Ptin ...

). Most species are small (7 mm or less), almost never exceeding 15 mm. This superfamily is traditionally considered to be the basal taxon within the

Aculeata Aculeata is a subclade of Hymenoptera containing ants, bees, and stinging wasps. The name is a reference to the defining feature of the group, which is the modification of the ovipositor into a stinger. However, many members of the group cannot ...

, and, as such, some species can sting, though the

venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a st ...

is harmless to humans. Members of the families

and

are the only

s among the

Hymenoptera Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typic ...

to have a life cycle in which the wasp larva begins its life inside the body of the host, and then later forms a sac (called a ''thylacium'') that protrudes out of the host's

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the to ...

. The closely related family

contains more traditional ectoparasitoids, attacking the

nymphs A nymph ( grc, νύμφη, nýmphē, el, script=Latn, nímfi, label=Modern Greek; , ) in ancient Greek folklore is a minor female nature deity. Different from Greek goddesses, nymphs are generally regarded as personifications of nature, are ...

webspinner The order Embioptera, commonly known as webspinners or footspinners, are a small group of mostly tropical and subtropical insects, classified under the subclass Pterygota. The order has also been called Embiodea or Embiidina. More than 400 s ...

s. The extinct, monotypic family

Plumalexiidae ''Plumalexius'' is a genus of wasps in the extinct monotypic family Plumalexiidae, containing two species: the type species ''Plumalexius rasnitsyni'', known from the Late Cretaceous White Oaks Pit in Sayreville, New Jersey, and ''Plumalexius ohm ...

was described in 2011 from fossils preserved in

Turonian The Turonian is, in the ICS' geologic timescale, the second age in the Late Cretaceous Epoch, or a stage in the Upper Cretaceous Series. It spans the time between 93.9 ± 0.8 Ma and 89.8 ± 1 Ma (million years ago). The Turonian is preceded b ...

age New Jersey amber.

References

External links

Online identification guide to eastern North American Chrysididae wasps
Apocrita superfamilies Late Cretaceous insects Cenozoic insects Turonian first appearances Extant Barremian first appearances {{Apocrita-stub