Flies belong to the order Diptera, a large, complex order of insects.
Unlike most insects, dipterans possess only one pair of functional wings; the hind wings are reduced to club-shaped structures called halters, which act as gyroscopic organs that assist in flight stability.
All dipteran flies undergo complete metamorphosis, with adults differing markedly in morphology, behaviors, and feeding habits from their larval stages. Consequently, parasitism can occur, either in the adult stage or the larval (maggot) stage.
Many dipteran fly species are of veterinary importance and vary greatly in size, feeding preferences, and the life stage responsible for parasitism or disease.
As adult parasites and vectors (eg, mosquitoes, flies, midges), dipteran flies feed on vertebrate blood or on secretions such as saliva, tears, and mucus. Dipterans can be broadly divided into dipterans with biting mouthparts and dipterans with nonbiting mouthparts. Many species are periodic parasites and serve as biological vectors or hosts of helminths, protozoa, bacteria, and viruses. Blood-feeding species can transmit pathogens of veterinary and medical importance, such as bluetongue virus in animals and dengue virus in humans, whereas nonbiting synanthropic flies can act as mechanical vectors of infectious agents.
As larval parasites (maggots), some dipteran flies develop in the skin, body cavities, or internal organs of living vertebrate hosts, producing a condition known asmyiasis. Depending on species, myiasis can be traumatic, furuncular, or migratory and can affect a wide range of domestic animals, wildlife, and humans.
For More Information
