Mosquito

Like all flies, mosquitoes go through four stages in their life-cycle: egg, larva, pupa, and adult or imago. Adult females lay their eggs in standing water, which can be a salt-marsh, a lake, a puddle, a natural reservoir on a plant, or an artificial water container such as a plastic bucket or a discarded bottle or tire. The first three stages are aquatic and last 5–14 days. Depending on the species and the ambient temperature, eggs hatch to become larvae, then pupae. The adult mosquito emerges from the pupa when it floats at the water surface. Bloodsucking species, depending on type, gender, and weather conditions can live as adults from a week to as long as several months. Some can overwinter as adults. (Source: Wikipedia.org)

If you didn't know that before, then now you know and maybe there is something you can do about it.

.