''Chaetorellia australis'' is a species of tephritid fruit fly known as the yellow starthistle peacock fly. It is used as an agent of

biological pest control Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also i ...

against the

noxious weed A noxious weed, harmful weed or injurious weed is a weed that has been designated by an agricultural or other governing authority as a plant that is injurious to agricultural or horticultural crops, natural habitats or ecosystems, or humans or liv ...

yellow starthistle ''Centaurea solstitialis'', the yellow star-thistle, is a species of thorny plant in the genus ''Centaurea'', which is part of the family Asteraceae. A winter annual, it is native to the Mediterranean Basin region and Invasive species, invasive ...

(''Centaurea solstitialis''). The adult fly is light golden yellow in color with small black spots on its body and stripes on its wings. The male fly is about 4 millimeters long and the female is slightly longer due to her large

ovipositor The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typica ...

. The female lays up to 240 cylindrical eggs beneath the bracts on the

flower head A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...

s of yellow starthistle. 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. Th ...

emerges and tunnels into the flower head, where it feeds on developing seeds. A larva might destroy up to 90% of the developing seeds inside a given flower head. It overwinters inside the head and

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 ...

tes into an adult fly. There are at least two generations per year. The first generation often utilizes the minor weed

cornflower ''Centaurea cyanus'', commonly known as cornflower or bachelor's button, is an annual flowering plant in the family Asteraceae native to Europe. In the past, it often grew as a weed in cornfields (in the broad sense of "corn", referring to gra ...

(''Centaurea cyanus'') before continuing reproduction on yellow starthistle. Sometimes the fly is difficult to introduce to an area if there is no cornflower growing nearby. ''C. australis'' generally occurs in low numbers and does not seem to have had much impact on starthistle seed production. This fly is native to southern Europe and the Mediterranean. It was first introduced to the United States for the purposes of biocontrol in 1988. It is now established throughout the northwestern United States.

Distribution

Poland Poland, officially the Republic of Poland, , is a country in Central Europe. Poland is divided into Voivodeships of Poland, sixteen voivodeships and is the fifth most populous member state of the European Union (EU), with over 38 mill ...

, to

Greece Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders wit ...

Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...

. Introduced to North America.

References

External links

Biocontrol Profile and links
Tephritinae Insects used for control of invasive plants Insects described in 1940 Diptera of Europe Diptera of North America {{Tephritinae-stub