Mosquito (from the Spanish and Portuguese meaning "small fly") is a common flying insect in the family Culicidae that is found around the world. There are about 3,500 species of mosquitoes. They are vectors for a number of infectious diseases that kill millions of people per year.

Mosquitoes go through four stages in their life cycle: egg, larva, pupa, and adult or imago. The first three stages are aquatic and last 5–14 days, depending on the species and the ambient temperature. The adult females can live up to a month (or more in captivity) but most probably do not live more than 1–2 weeks in nature.

Mosquito larvae have a well-developed head with mouth brushes used for feeding, a large thorax with no legs and a segmented abdomen.

Larvae breathe through spiracles located on the 8th abdominal segment and therefore must come to the surface frequently. The larvae spend most of their time feeding on algae, bacteria, and other microorganisms in the surface microlayer. They dive below the surface only when disturbed. Larvae swim either by jerky movements of the entire body, explaining their nickname "wigglers", or through propulsion with the mouth brushes. Larvae also like very warm temperatures.

Larvae develop through 4 stages, or instars, after which they metamorphose into pupae. At the end of each instar, the larvae molt, shedding their exoskeleton, or skin, to allow for further growth.

Content Resource : http://en.wikipedia.org/wiki/Mosquito.