McHenry County Department of Health - Environmental Health
Translate this page:

Mosquito Life Cycle

Press Enter to show all options, press Tab go to next option

Mosquito eggs develop in any standing water that lasts more than 5 to 7 days.  To reduce the mosquito population around your home, eliminate standing water and debris.

The mosquito goes through four stages during its life cycle: 

  • Egg
  • Larva
  • Pupa
  • Adult Mosquito

The eggs normally hatch into larvae within 48 hours.  Larvae live in water from 7 to 14 days depending on the water temperature.  During this time, the larva molts 3 times and grows to almost 1 cm.  After the larva molts the fourth time it becomes a pupa.  The pupa is lighter than the water and floats on the water surface.  In 1 to 4 days, the adult mosquito emerges out of the pupa.  Its rests on the water surface until its body dries and hardens enough to fly away.

Mosquito Laying Eggs Eggs 
In the case of the Culex Mosquito, the eggs are attached together to form rafts that float on the surface of the water.
Larval Stage Mosquitos
Larva live in the water and come to the surface to breathe. Most Larvae have siphon tubes for breathing and hang upside down from the water surface. Larvae shed their skin 4 times, growing larger with each
Pupal Stage Mosquitos
The pupal stage is a resting, non feeding stage. When development is complete the pupal skin splits open and the adult mosquito emerges.
Adult Mosquito
The new adult rests on the surface of the water to allow its body to dry and all its body parts to harden. Blood feeding and mating does not occur for 2 to 3 days.