At this point in the life cycle, mosquitoes are the hardest and most costly to control. This is due in part to the fact that in order for the pesticides sprays to work, the mosquito must be flying when they come into contact with it. It should be noted that only female mosquitoes bite, and if you are in the presence of mosquito activity, wear a bug spray that contains DEET.
Image 1: Ochlerotatus sollicitans
Source: Bug Guide
Image 2: Aedes albopictus (asian tiger)
Source: CDC Public Health Image Library
After taking a blood meal, female mosquitoes deposit eggs on or near the surface of standing water bodies. These eggs are usually deposited together as "egg rafts." A few species of mosquitoes do not lay eggs in "egg rafts"; rather, they opt to lay eggs in flood prone areas for later development. To avoid heavy mosquito infestations, empty any items that may be holding standing water. This must be a neighborhood effort, as mosquitoes that breed in neighboring yards will travel to seek new harborage and new hosts. Shown here are 2 different types of mosquito eggs. Depending on the species of mosquito, female mosquitoes will lay eggs like those pictured.
Note - photos are under magnification.
Image 1: University of Hawaii at Hilo
Image 2: Los Angeles County West Vector and Vector-Borne Disease Control District
As larva, mosquitoes require water and are the easiest to destroy. This is due to the fact they are most vulnerable during their developmental stages, as well as the fact that they are easy to find, in areas of standing water. It should be noted that larvaciding is more successful and cheaper than using the spray rig mounted on the back of a truck. Pictured to the left, a mosquito larva under microscope. Depending on the species certain features shown in this photo will vary. Mosquito larvae spend this stage in water where they forage for food.
At this stage in the mosquito life cycle, mosquitoes don't feed. Depending upon temperatures, mosquitoes usually spend 1-4 days at this stage, until hatching into the adult mosquito. They are lighter than the water and simply float to the surface to rest and breathe through tiny, horn-like features called trumpets. The body is translucent allowing the developing adult mosquito to be seen.