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MOSQUITOES |

Mosquitoes are not only pests; they are a major health hazard,
with hundreds of annual deaths attributed to mosquito-borne disease.
Mosquitoes are actually the world's deadliest animal having caused more deaths than all wars combined!
Mosquitoes are insects that belong to the order Diptera, the True
Flies. Mosquitoes differ from other flies inthat mosquito wings have
scales. Female mosquitoes' mouthparts form a long antennae
(proboscis) for piercing and sucking. Males differ from females by
having feathery antennae and mouthparts not suitable for piercing
skin. Blood-feeding females usually must ingest a blood meal in
order to develop eggs. Saliva injected by females while engorging on
blood causes itching. Males, as well as females, sip nectar,
honeydew and fruit juices. There are over 2500 different species of
mosquitoes throughout the world; about 200 species occur in the
United States with about 55 species of mosquitoes occurring in Texas
and 77 species in Georgia and Florida.
The Name "Mosquito"
"Mosquito" is a Spanish word meaning "little fly". The Spanish
originally called mosquitoes "musketas," and native Hispanic
Americans called them "zancudos" meaning "long-legged". The two
words apparently combined to form "mosquito" in Spanish North
America and dates back to the late 1500's. What is the correct
plural form of the word mosquito? In Spanish it would be
"mosquitos," but in English "mosquitoes" (with the "e") is correct.
Mosquitoes can be an annoying pest or a very serious problem. They
interfere with work and spoil hours of leisure time. Their attacks
on farm animals can cause sickness and decreased production. We best
know mosquitoes for their role in the transmission of diseases, such
as malaria, yellow fever, dengue fever, encephalitis and West Nile
virus. Of these, malaria is by far the most important. According to
recent data released by the World Health Organization and the
Centers for Disease Control, mosquitoes infect a minimum of 500
MILLION people with the disease each year, and more than two million
-- mostly children in sub-Saharan Africa -- die of it.
The mosquito goes through four separate and distinct stages of
its life cycle: Egg, Larva, Pupa, and Adult. Each stage is easily
recognized by its special appearance. The egg, larva and pupa stages
depend on temperature and species characteristics to determine how
long they take for development.
LIFE CYCLE
Egg
Eggs are laid one at a time or more commonly attached together to
form "rafts" where they float on the surface of the water. The more
commonly known Culex species, lays its eggs together in rafts of up
to 200 eggs or more. Other species lay their eggs singly. Some lay
their eggs on the surface of the water while others lay their eggs
on damp soil later to be flooded by water. Most eggs hatch into
larvae within 48 hours. Water is necessary to their habitat.
Larva
Once hatched, the larva (plural - larvae) lives in the water and
comes to the surface to breathe. Most larvae hang upside down from
the surface of the water and use siphon tubes for breathing while
some attach to plants for oxygen. Larvae shed their skins, referred
to as molting, four times during this stage and grow larger after
each molt. Larvae depend on microorganisms and organic matter in the
water for a food sources. It is during the fourth molt that the
larva transforms into a pupa. Larvae live in water from 4 to 14 days
depending on water temperature.
Pupa
The pupal stage is a resting, non-feeding developmental stage.
During this stage, pupae are mobile and respond to changes in light.
They move by flipping or wagging their tails to move towards
protected areas. This is the stage in which the mosquito changes
into an adult. This process is similar to a caterpillar developing
into an adult butterfly while in the cocoon. This takes about two
days for the Culex species. The adult mosquito emerges after
development is complete. Pupae may live in water 1 to 10 days
depending on species and water temperature.
Adult
The newly emerged adult rests on the surface of the water for a
short time to allow itself to dry and all its body parts to
harden. It cannot fly unless its wings are spread and dried
properly. Blood feeding and mating will not occur until a
couple of days after it has emerged. Mating usually occurs near
the emergence site, and the male dies shortly after.
BITING
Only female mosquitoes require a blood meal (protein) and bite
animals - warm or cold blooded - and birds. Male mosquitoes do
not bite, but feed on the nectar of flowers or other sources of
liquid carbohydrates. Both male and female mosquitoes are
primarily nectar feeders. Horses, cattle, smaller mammals
and/or birds are the preferred blood sources for those female
mosquitoes that are capable of blood feeding; humans are
secondary. Some adult mosquitoes may live a few weeks or
longer.
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