Mosquitoes are common insects in our surroundings. They found in damp and marshy places. The female mosquitoes feed on the blood of human beings and other vertebrates. The male mosquitoes suck juices of flowers and plants. These are harmful insects as they spread diseases like malaria, typhoid and other diseases.
Mosquitoes are many types some of them are Anopholes and Culex.
Life history of mosquito:
The mosquito life history contains four stages they are.
1.) Egg
2.) Larva
3.) Pupa
4.) Imago
Egg: An adult female mosquito lays about 300 eggs in the ponds and pools. Each egg is in cigar shaped. The eggs are laid side by side and held together by a sticky substance in the form of a boot-shaped raft. In one to three days, the eggs hatch and a larva come out of egg.
larva: The larva of mosquitoes are called Wrigglers because they move in the wriggling movement. The body is segmented has head, thorax and abdomen. The head has a pair of eyes and a pair of antenna. Each eye is made up of many small eyes. Hence it is called as compound eye. There are a pair of feeding brushes. The feeding brushes are made up of a stiff hairs. The feeding brushes cause small currents of water by which small particles of food are taken in to mouth. The thorax is globular and the abdomen is slender with 9 segments. On the thorax and abdomen here are stiff hairs. The abdomen has a tube on the eight segment, through which air is taken. This is called the respiratory siphon. The larva periodically comes to the surface of water and takes through respiratory siphon. The larvae feed on algae and small organic particles and grow.
Pupa: The pupa is in comma(,) shaped and is called a tumbler. The head and thorax are fused on this a pair of tubes called respiratory trumpets are present. The pupa hangs in the surface water and takes in atmospheric air by these respiratory trumpets. Depending on the temperature the pupa stage lasts from two to seven days.
Imago: This is the final stage in the life cycle of mosquito where pupa is changed in to newly adult mosquito.
Diseases caused by mosquito: Different types of mosquitoes cause different diseases in human beings. Malaria is a deadly human disease. It is caused by female anopheles mosquito. When a female anopheles bites a human being, the malarial parasites are introduced in to human body. Aedes mosquito transmits yellow fever and Dengue fever. Culex mosquito transmit the filariasis or elephantiasis disease to man.
Prevention: To prevent mosquito bite, mosquito nets are to be used. It is cheaper and a better way to control malaria. Mosquito repellants also keep the mosquitoes away. Now-a-days a variety of mosquito repellants are available in market. Adult mosquitoes can be destroyed by spraying insecticides. It is easy to kill the larvae of mosquitoes than the adults. When the breeding places of mosquitoes are sprayed with kerosene it forms a thin film above the water. The larvae get suffocated and die. Our surroundings should be kept clean, and dry. Water should not be allowed to stagnate in vessels, pots or drums.