''Microplitis croceipes'' is a braconid wasp native to the US state of

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

. It is an important

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 ...

of caterpillars, including those of major agricultural pests ''

Helicoverpa zea ''Helicoverpa zea, ''commonly known as the corn earworm, is a species (formerly in the genus ''Heliothis'') in the family Noctuidae. The larva of the moth ''Helicoverpa zea'' is a major agricultural pest (organism), pest. Since it is polyphagous ...

'' (formerly called ''Heliothis zea'') and ''

Heliothis virescens ''Chloridea virescens'', commonly known as the tobacco budworm, is a moth of the family Noctuidae found throughout the eastern and southwestern United States along with parts of Central America and South America. It is a major pest of field crop ...

''. ''Microplitis croceipes'' uses its antennae to detect the odor of caterpillar

frass Frass refers loosely to the more or less solid excreta of insects, and to certain other related matter. Definition and etymology ''Frass'' is an informal term and accordingly it is variously used and variously defined. It is derived from the ...

, or

feces Feces (also known as faeces American and British English spelling differences#ae and oe, or fæces; : faex) are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the ...

. The wasp deposits a single egg inside the caterpillar; as the wasp larvae mature they feed on the caterpillar, which weakens and dies after the larvae emerge and pupate. The wasp larvae then spin cocoons and pupate inside them. Adult wasps emerge after a week. Because the

olfactory system The olfactory system, is the sensory nervous system, sensory system used for the sense of smell (olfaction). Olfaction is one of the special senses directly associated with specific organs. Most mammals and reptiles have a main olfactory system ...

of ''M. croceipes'' is linked to its taste receptors, wasps can be trained to respond to the smell of an arbitrary chemical if the smell is repeatedly presented in association with food (sugar water or caterpillars). The smell of "food" triggers a characteristic pattern of activity, a short-range host-seeking response. Researchers have said that ''M. croceipes'' has great potential for use as a biological sensor "due to its ability to be conditioned, respond and discriminate target odors from background odors." The Wasp Hound "portable nose" device depends on trained ''M. croceipes'' as its biosensor.

References

{{Taxonbar, from=Q6839928 Braconidae Hymenoptera of North America Insects described in 1872 Taxa named by Ezra Townsend Cresson Insects used as insect pest control agents Biological pest control wasps