CULEX, AEDES, AND ANOPHELES

Both adult male and female mosquitoes feed on nectar and other sources of sugar for energy, but adult female mosquitoes also bite humans and animals for a bloodmeal to produce eggs. The mosquito species identified below pose health risks for both humans and animals in the Pacific Southwest.

Culex Mosquitoes

WESTERN ENCEPHALITIS MOSQUITO
Culex tarsalis

NORTHERN HOUSE MOSQUITO
Culex pipiens

SOUTHERN HOUSE MOSQUITO
Culex quinquefasciatus

Culex mosquitoes can carry and spread pathogens that are responsible for diseases in both humans and animals.

It takes about 7-10 days for an egg to develop into an adult mosquito.

Eggs

  • Adult female mosquitoes lay eggs on the surface of fresh or stagnant water. Water sources can include barrels, horse troughs, ornamental ponds, unmaintained swimming pools, puddles, creeks, ditches, and marshy areas.
  • A female Culex mosquito lays eggs one at a time. Eggs stick together to form a raft of 100 to 300 eggs. The raft floats on the water.

Larva

  • Larvae hatch from mosquito eggs and live in water.
  • Larvae can be seen in the water. They are very active and are often called “wigglers.”
  • They feed on a variety of things found in the water.
  • Larvae shed their skin (molt) several times during this stage.

Pupa

  • Pupae live in water. Pupae do not have external mouthparts and do not feed during this stage.
  • An adult mosquito emerges from a pupa and flies away.

Adult

  • Adult female mosquitoes bite people and animals. Mosquitoes need blood to produce eggs.
  • After blood feeding, female mosquitoes look for water sources to lay eggs. Several days pass between feeding and looking for a place to lay eggs.
  • Culex mosquitoes don’t fly long distances but have been known to fly up to 2 miles (3.2 km).
  • Some Culex mosquitoes prefer to live near and bite birds. They bite people when other animals are not nearby.
  • Because Culex bite animals and people, they live outdoors or near homes.

Centers for Disease Control and Prevention (CDC):

Aedes Mosquitoes

YELLOW FEVER MOSQUITO
Aedes aegypti

ASIAN TIGER MOSQUITO
Aedes albopictus

Aedes mosquitoes can carry and spread pathogens that are responsible for diseases in both humans and animals.

It takes about 7-10 days for an egg to develop into an adult mosquito.

Eggs

  • Adult, female mosquitoes lay eggs on the inner walls of containers with water, above the waterline.
  • Eggs stick to container walls like glue. They can survive drying out for up to 8 months. Mosquito eggs can even survive a winter in the southern United States.
  • Mosquitoes only need a small amount of water to lay eggs. Bowls, cups, fountains, tires, barrels, vases, and any other container storing water make a great “nursery.”

Larva

  • Larvae live in the water. They hatch from mosquito eggs. This happens when water (from rain or a sprinkler) covers the eggs.

  • Larvae can be seen in the water. They are very active and are often called “wigglers.”

Pupa

  • Pupae live in the water. An adult mosquito emerges from the pupa and flies away.

Adult

  • Adult female mosquitoes bite people and animals. Mosquitoes need blood to produce eggs.

  • After feeding, female mosquitoes look for water sources to lay eggs.

  • Ae. aegypti and Ae. albopictus don’t fly long distances. In its lifetime, these mosquitoes will only fly within a few blocks.

  • Ae. aegypti mosquitoes prefer to live near and bite people.
  • Because Ae. albopictus mosquitoes bite people and animals, they can live in or near homes or in neighboring woods.
  • Ae. aegypti mosquitoes live indoors and outdoors, while Ae. albopictus live outdoors.

Centers for Disease Control and Prevention (CDC): 

Anopheles Mosquitoes

WESTERN MALARIA MOSQUITO
Anopheles freeborni

Anopheles mosquitoes can carry and spread pathogens that are responsible for diseases in both humans and animals.

The duration from egg to adult varies considerably among species and is strongly influenced by ambient temperature. Mosquitoes can develop from egg to adult in as little as 7 days but usually take 10-14 days in tropical conditions.

Eggs

  • Eggs are laid singly directly on water and are unique in having floats Top: Anopheles Egg; note the lateral floats. Bottom: Anopheles eggs are laid singlyon either side.
  • Eggs are not resistant to drying and hatch within 2-3 days. Hatching may take up to 2-3 weeks in colder climates.

Larva

  • Larvae hatch from mosquito eggs and live in water. 
  • In contrast to other mosquitoes, Anopheles larvae lack a respiratory siphon (breathing tube) so they have to position their body to be parallel to the water surface.
  • Larvae feeds on algae, bacteria, and other microorganisms found in the water.
  • Larvae dive below the surface only when disturbed.
  • Larvae shed their skin (molt) four times during this stage.

Pupa

  • Pupae live in water and does not feed during this stage.
  • As with the larvae, pupae must come to the surface frequently to breathe.
  • An adult mosquito emerges from a pupa and flies away.

Adult

  • Adult mosquitoes usually mate within a few days after emerging from the pupal stage. 
  • Adult female mosquitoes feed on sugar sources for energy. They usually bite humans and animals for blood to produce eggs.
  • After feeding, female mosquitoes will rest for a few days before they look for water sources to lay the eggs.
  • Females can survive up to a month (or longer in captivity) but most do not live longer than 1-2 weeks in nature.

Centers for Disease Control and Prevention (CDC):