Life-cycle of Anopheles mosquitoes

Wednesday, 19/10/2016

Anopheles is a parasite that belongs to the class of mosquitoes discovered in 1818 and it was named by J. W. Meigen. Its sole goal is in the transmission of the dangerous malaria parasite species into human bodies. A bite of Anopheles mosquitoes results in Malaria. Basically, female mosquitoes of the class Anopheles are the reasons of transmission of malaria in human body. The Female Anopheles mosquito takes the blood as a meal to help out in reproduction, and the bool is a resource for parasite’s life cycle.


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According to the research about genus classification, there are approximately 430 sub classes of Anopheles, out of which only 30 to 40 causes malaria. Anopheles’ are mainly found throughout the world except in Antarctica. Depending upon the region and the environment, Anopheles’ that can cause malaria are found not only in malaria-endemic areas, but also in areas where malaria has been vanished or not common among people for years and years. Such of these areas are thus constantly at the danger level of getting the re-introduction of this disease.


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SOURCE- http://www.cdc.gov/malaria/about/biology/mosquitoes/map.html

Now let’s read about the life cycle of this mosquito.

LIFE STAGES OF ANOPHELES MOSQUITO

Like each and every mosquito, there exists a life cycle of anopheles too. They have to go through the four stages in their life cycle too. The phases are as follows:
●egg,
●larva,
●pupa,
●adult

The first three stages of its life cycle are termed as aquatic and they last for 5-14 days, depending upon the class of Anopheles and on the current temperature. The last stage that’s the adult stage start when the female Anopheles mosquito acts as a malaria causing factor. The adult females have a survival range of up to a month or more. But they can’t survive more than 1 to 2 weeks.


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1.EGGS

●The number of eggs laid by an adult female is approximately 50 to 200 eggs.

●The laid eggs are unique as they have floats on either sides and also they are laid individually directly on water.

●Eggs are anti-resistant to drying and within a time-period of 2 to 3 days they start hatching.

● Although during winters or cold temperature, hatching process may boost up to 2 to 3 weeks.

2.LARVAE

●After the process of hatching, the next phase is formation of mosquito larvae that is a well-developed head, mouth brushes, a large thorax and an abdomen is clearly visible without any legs up till now.

●The difference between other mosquitoes and Anopheles is that Anopheles does not have a respiratory siphon and hence their bodies are parallel to the surface of water.

●Spiracles are the only source for breathing process for a larva. Spiracles are located on the 8th abdominal segment in their bodies.

● Larvae feeds on algae, bacteria, and other microorganisms.

●Larvae further develops through four more phase, after these four phase they get turned into some pupae.

●Larvae are mainly found mainly in water marshes, mangrove swamps, rice fields, grassy ditches, streams and rivers edges, and in small &temporary rain pools or pounds.

3.PUPAE

●When it is viewed from the side pupa is a comma-shaped.

●In this phase the head and thorax are much more visible and are under abdomen covering.

●Similarly, like larvae, pupa also comes to surface for breathing.

●After few days the whole covering splits and an adult mosquito is emerged from it.

On an average, a mosquito life cycle from egg to adult is completed within 4 to 5 days, but in cold climate conditions it may take 10 to 12 days.

4.ADULT

●Anopheles adult have three sections like all other mosquitoes:
Head
Thorax
Abdomen

●The head is specialized for the purpose of getting sensory information and for feeding. It contains the eyes and a pair of long, many-segmented antennae. The head also has a long, straight-projecting proboscis necessary for feeding, and have two
sensory palps.

The antennae are essential for:

●detecting host odors

● odors of areas where females lay eggs.

●The thorax is required for locomotion. The part attached to the thorax are 3 pairs of legs and a pair of wings.

●The abdomen is necessary for food digestion and egg development phase. The adult male and female mosquitoes mate again and this life cycle is again in active state.