Encarsia formosa | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Hymenoptera |
Family: | Aphelinidae |
Subfamily: | Coccophaginae |
Genus: | Encarsia |
Species: | E. formosa |
Binomial name | |
Encarsia formosa Gahan, 1924 | |
Encarsia formosa is a species of chalcidoid wasp and a well known parasitoid of greenhouse whitefly, one of the first to be used commercially for biological pest control, from the 1920s. They can use at least 15 species of whitefly as a host, including Bemisia tabaci and Aleyrodes proletella. [1]
The tiny females (about 0.6 mm long) are black with a yellow abdomen and opalescent wings. This species reproduces asexually via thelytoky induced by Wolbachia infection. [1] Males are produced only rarely. They are slightly larger than females and are completely black in coloration.
Females deposit 50-100 eggs individually inside the bodies of nymphs or pupae of the host species. The wasp larvae develop through four instars in about two weeks at optimum temperatures. Parasitized greenhouse whitefly pupae turn black in about 10 days, while parasitized sweet potato whiteflies turn amber brown. Both are easily distinguished from unparasitized host pupae. Wasp pupation occurs within the whitefly body. Adult wasps emerge about 10 days later.
Encarsia formosa has been used as a natural pesticide to control whitefly populations in greenhouses since the 1920s. Use of the insect fell out of fashion due to the increased prevalence of chemical pesticides and was essentially non-existent by the 1940s. Since the 1970s E. formosa has seen something of a revival, with renewed usage in European and Russian greenhouses. [1] In some countries, such as New Zealand, it is the primary biological control agent used to control greenhouse whiteflies, particularly on crops such as tomato, a particularly difficult plant for predators to establish on. [2]
E. formosa utilizes the clap and fling mechanism often seen in sub-mm insects. The wings, at the apex, and nearly touching, fling apart and generate strong vortices along the leading edge and wing tips. This mechanism works well in low Reynolds number flight as the generated vortices remained attached through the stroke cycle. Flexible wings and bristles along the wing edges help mitigate the large drag forces that the insect must overcome. Unlike normal flight, this method would work in an entirely inviscid medium, as it does not rely on a starting vortex to create circulation about the wing. [3] [4] [5] [6] [7] [8]
Butterflies are insects that have large, often brightly coloured wings, and a conspicuous, fluttering flight. The group comprises the superfamilies Hedyloidea and Papilionoidea. Butterfly fossils date to the Paleocene, about 56 million years ago.
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Trialeurodes vaporariorum, commonly known as the glasshouse whitefly or greenhouse whitefly, is an insect that inhabits the world's temperate regions. Like various other whiteflies, it is a primary insect pest of many fruit, vegetable and ornamental crops. It is frequently found in glasshouses (greenhouses), polytunnels, and other protected horticultural environments. Adults are 1–2 mm in length, with yellowish bodies and four wax-coated wings held near parallel to the leaf surface.
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Torkel Weis-Fogh was a Danish zoologist and Professor at the University of Cambridge and the University of Copenhagen. He is best known for his contributions to the understanding of insect flight, especially the clap and fling mechanism used by very small insects. James Lighthill named this "the Weis-Fogh mechanism of lift generation".
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Around 350 BCE, Aristotle and other philosophers of the time attempted to explain the aerodynamics of avian flight. Even after the discovery of the ancestral bird Archaeopteryx which lived over 150 million years ago, debates still persist regarding the evolution of flight. There are three leading hypotheses pertaining to avian flight: Pouncing Proavis model, Cursorial model, and Arboreal model.
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Encarsia is a large genus of minute parasitic wasps of the family Aphelinidae. The genus is very diverse with currently about 400 described species and worldwide distribution. The number of existing species is expected to be several times higher because many species are still undescribed. Encarsia is a very complex genus, with specimens showing both inter- and intra-specific variations, making morphological classification difficult.
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Encarsia inaron is a parasitoid wasp used in the control of ash whitefly, Siphoninus phillyreae. The ash whitefly is an insect from Europe that feeds on the sap of plants, and which has become a pest in North America. E. inaron was acquired from Italy and Israel and brought to California in 1989.
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Adrian Leland Rees Thomas is a professor of biomechanics at the University of Oxford and Director of Studies in Biological Sciences at Lady Margaret Hall, Oxford running the Animal Flight Research Group. He is co-founder and Chief Scientific Officer at Animal Dynamics and is also chairman of the flight section of the Bionis International Biomimetics Network.
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