Fly

Fly, insect of the order Diptera, characterized by the presence of only 1 pair of wings. Well-known species include the common house fly, mosquitoes, and gnats. Many flies are known to transmit diseases such as malaria and dysentery, while others are beneficial as pollinators and as laboratory specimens in genetic studies. Approximately 100,000 varieties are found worldwide, ranging in size from 1/20 in (1.3 mm) to 3 in (7.6 cm).