''Chrysolina hyperici'', the Saint John's wort beetle is a species of beetles of the family

Chrysomelidae The beetle family Chrysomelidae, commonly known as leaf beetles, includes over 37,000 (and probably at least 50,000) species in more than 2,500 genera, making it one of the largest and most commonly encountered of all beetle families. Numerous s ...

.Bugguide.net. Species ''Chrysolina hyperici'' - St. Johnswort Beetle
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Life cycle

The species lays up to 2,000 eggs on the host plant during the early fall. They lay their eggs on the undersides of leaves of new fall basal growth on its host plant, St. John's Wort (''

Hypericum perforatum ''Hypericum perforatum'', commonly known as St. John's wort (sometimes perforate St. John's wort or common St. John's wort), is a flowering plant in the family Hypericaceae. It is a hairless, Perennial, perennial herb with woody Root, roots, y ...

''). The larvae feed for a month on the leaves, emerging at night and hiding during the day. When full grown they move to the soil to pupate. After two weeks they emerge as adults. In the spring the adults feed upon new growth of their host plant.

Taxonomy

The species is most often classified as ''Chrysolina hyperici'' (Forster, 1771), however it was originally placed in the genus '' Chrysomela'' as ''Chrysomela hyperici''. It was first scientifically described and named by

Johann Reinhold Forster Johann Reinhold Forster (; 22 October 1729 – 9 December 1798) was a German Reformed pastor and naturalist. Born in Tczew, Dirschau, Pomeranian Voivodeship (1466–1772), Pomeranian Voivodeship, Polish–Lithuanian Commonwealth (now Tczew, Po ...

in ''Novæ species insectorum'' in the year 1771. Within the genus '' Chrysolina'', the species is classified in the subgenus '' Hypericia''. It is closely related to the species '' Chrysolina quadrigemina''.

Names

''Chrysolina hyperici'' is most often known in English by the common names "St. Johnswort Beetle", "Saint John's Wort Beetle" or close variations. In the United States ''C. hyperici'' is also known by the common name "klamathweed beetle" from one of the common names of ''Hypericum perforatum''.

Distribution

Originally distributed in Europa and Asia, it has been introduced in other places as

biological control Biological control or biocontrol is a method of controlling pests, whether pest animals such as insects and mites, weeds, or pathogens affecting animals or plants by using other organisms. It relies on predation, parasitism, herbivory, or o ...

of ''

''.Richard E. White. ''A Field Guide to the Beetles of North America''. Boston: Houghton Mifflin, 1983. . P. 296.

References

Chrysomelinae Biological pest control beetles Beetles described in 1771 Taxa named by Johann Reinhold Forster {{Chrysomelinae-stub