fruit fly, common name for any of the flies of the families Tephritidae and Drosophilidae. All fruit flies are very small insects that lay their eggs in various plant tissues. The Tephritidae contains about 1,200 species characterized by wide heads, black or steely green or blue bodies, iridescent greenish eyes, and wings that are usually mottled brown or black. The eggs of most species are laid directly in the pulp of the fruit on which the larvae feed; in North America, blueberries, cherries, and apples are much damaged by these insects. In warm regions, the Mediterranean fruit fly, Ceratitis capitata, was a serious pest of citrus fruits; it has now been eradicated from the S United States. Some species, e.g., the goldenrod gall fly, Eurosta solidaginis, which deposits its eggs in species of goldenrod, lay their eggs in plants of no economic importance. The Drosophilidae, or pomace flies, are yellowish and in the wild are largely found around decaying vegetation. The larvae living in fruit actually feed on the yeasts growing in the fruit. Drosophila melanogaster, also called vinegar fly, is a much used laboratory insect; its 10-day life cycle and large chromosomes, particularly those of the salivary glands of the larva, have made it invaluable in the study of genetics. Fruit flies are classified in the phylum Arthropoda, class Insecta, order Diptera, families Tephritidae and Drosophilidae.

Mediterranean fruit fly: see fruit fly.

Any dipteran species of two families: large fruit flies (Trypetidae) and small fruit flies, or vinegar flies (family Drosophilidae; see drosophila). The larvae feed on fruit or other vegetation. The adults' wings are banded or spotted with brown. Many species attack cultivated fruits, sometimes causing enough damage to create significant economic loss. Some species are leaf miners; others burrow in plant stems. Well-known fruit-fly pests include the Mediterranean fruit fly and the apple maggot of the U.S., the Mexican and Oriental fruit flies, and the olive fruit fly of the Mediterranean region.

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or Med fly

Fruit fly (Ceratitis capitata) proven to be particularly destructive to citrus crops, at great economic cost. The Med fly lays up to 500 eggs in citrus fruits (except lemons and sour limes), and the larvae tunnel into the fruit, making it unfit for human consumption. Because of this pest, quarantine laws regulating fruit importation have been enacted worldwide.

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