Mosquitoes are a group of about 3500 species of small insects that are a type of fly (order Diptera). The word “mosquito” (formed by mosca and diminutive -ito) is Spanish for “little fly”. Mosquitoes have a slender segmented body, a pair of wings, three pairs of long hair-like legs, feathery antennae, and elongated mouthparts.
Mosquitoes diverged from other insects about 226 million years ago. Fossils of primitive mosquitoes have been found that are over 90 million years old; fossils similar to modern mosquitoes, 79 million years old; fossils identical to modern mosquitoes, 46 million years old. The life cycle consists of the egg, larva, pupa, and adult. Eggs are laid on the water surface; they hatch into motile larvae which feed on aquatic algae and organic material; pupae are breathing non-flying primitive adults.