Fly - Order Diptera

Order Diptera

The presence of a single pair of patent, metathoracic flight wings distinguishes most true flies from other insects with "fly" in their names, such as mayflies, dragonflies, damselflies, stoneflies, whiteflies, fireflies, alderflies, dobsonflies, snakeflies, sawflies, caddisflies, butterflies or scorpionflies. However, some true flies have become secondarily wingless, for example many members of the superfamily Hippoboscoidea and some species that are inquilines in social insect colonies.

Some authors draw a distinction in writing the common names of insects. True flies are written as two words, such as crane fly, robber fly, bee fly, moth fly, and fruit fly. In contrast, common names of nondipteran insects that have "fly" in their names are written as one word, e.g., butterfly, stonefly, dragonfly, scorpionfly, sawfly, caddisfly, whitefly. In practice however, though it is practical this is a comparatively new convention; especially in older books, one commonly might see the likes of "saw fly" and "caddis fly", or hyphenated forms such as house-fly and dragon-fly. In any case, non-entomologists cannot in general be expected to tell dipterans, "true flies", from other insects, so it would be unrealistic to expect rigour in the use of common names.

The Diptera comprise a large order, containing an estimated 240,000 species of mosquitoes, gnats, midges and others, although under half of these (about 120,000 species) have been described. It is one of the major insect orders both in terms of ecological and human (medical and economic) importance. The Diptera, in particular the mosquitoes (Culicidae), are of great importance as disease transmitters, acting as vectors for malaria, dengue, West Nile virus, yellow fever, encephalitis and other infectious diseases.