''Aphytis melinus'' is an internal parasite of the California red scale, ''

Aonidiella aurantii ''Aonidiella aurantii'' or red scale is an armored scale insect and a major pest of citrus. It is thought to be a native of South China but has been widely dispersed by the agency of man through the movement of infected plant material. In the ...

'', which is a pest of

citrus ''Citrus'' is a genus of flowering plant, flowering trees and shrubs in the rue family, Rutaceae. Plants in the genus produce citrus fruits, including important crops such as Orange (fruit), oranges, Lemon, lemons, grapefruits, pomelos, and lim ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and elsewhere. This wasp drums its antennae against the

scale insect Scale insects are small insects of the order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient grouping than the ...

to find out if it is healthy, if it is already parasitized, how large it is, etc., to decide how to use this prey. It has four choices (from worst to best): leave the scale to keep searching, feed directly on the scale, use the scale as a host for a male ''A. melinus'', or use the scale for a female ''A. melinus''. If it accepts the scale as a host, the female will lay an egg in the host. When the egg hatches, the

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

l wasp consumes the internal organs of the pest. When finished with its host, the larva enters the

pupa A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their ...

l, or cocoon, stage. From the pupa emerges the

adult An adult is a human or other animal that has reached full growth. In human context, the term ''adult'' has meanings associated with social and legal concepts. In contrast to a " minor", a legal adult is a person who has attained the age of major ...

wasp, smaller than the scale it consumed, which goes off in search of more scale insects. This beneficial insect has controlled a key pest in citrus, significantly reducing

pesticide Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampri ...

use on citrus in California.

References

Aphelinidae Insects described in 1959 {{Chalcidoidea-stub