Mosquitoes – Diptera


Identification & Description:

The mosquito is a member of the family Culicidae; these insects have a pair of scaled wings, a pair of halteres, a slender body, and long legs. The females of most mosquito species suck blood from other animals. Size varies but is rarely greater than 15 mm (0.6 inch). Mosquitoes weigh only about 2 to 2.5 mg (0.03 to 0.04 grain). They can fly at about 1.5 to 2.5 km/h (0.9 to 1.6 mph) and most species are nocturnal.

The family Culicidae belongs to the order Diptera and contains about 3500 species in three subfamilies: Anophelinae (3 genera), the Culicinae (9 genera and >80% of all the species) and the Toxorhynchitinae (1 genus). The genera include Anopheles, Culex, Psorophora, Ochlerotatus, Aedes, Sabethes, Wyeomyia, Culiseta, and Haemagoggus. Within the family Anophelinae six subgenera are recognized: Stethomyia, Lophopodomyia, Kerteszia, Nyssorhynchus (all South American), Cellia (Old World only) and Anopheles (worldwide).

Mosquitos are principally nectar feeders with only the females requiring a meal of blood. In contrast to this rule the Toxorhynchites never drinks blood. This family includes the largest of the extant mosquitoes (colloquially referred to as “mosquito eaters”) and their larvae are predatory on the larvae of other mosquitoes. Attempts have been made in the past to use these as mosquito control agents but with variable success.

Mosquito is a Spanish word meaning “little fly”, with its use dates back to about 1583. Before then, they were called “biting flies” in English, but the term “mosquito” was adopted to prevent confusion with the house fly. The word derives from Sanskrit maksh (fly) via the Latin word musca (fly) and the Italian moschetta or Spanish mosquito (little fly). The French word is moustique.

The attack:
When the female mosquito pierces the skin, she injects a bit of saliva into the wound before drawing blood (which is later used to develop eggs). The itchy, swollen welt that forms after the bite is an allergic reaction to the saliva that was left in the wound. The welts last between a few hours and a few days on people who are highly sensitive to the bites. If scratched, the bites can lead to infection transferred from the fingernails.

But these insects are more than just a minor nuisance. In fact they are reported to have killed more people than any other insect in the world. These blood-sucking insects are responsible for transmitting killer diseases such as malaria, viral encephalis, yellow fever and dengue fever to both animals and humans. Dengue fever can lead to dengue hemmoragic fever that may cause shock, bleeding and eventually death. Malaria also causes flu-like symptoms including vomiting, sweating and joint pain. Although the disease is curable, if discovered in its early stages, up to 1.5 million people in Africa, Asia and Latin America die from the tropical parasitic disease each year. Encephalitis is caused by a viral infection that leads to inflammation of the brain cells and surrounding membranes. The brain tissue eventually swells, causing internal bleeding and brain damage.

The female mosquito (in almost all species) sucks the blood of mammals, including humans — commonly referred to (incorrectly) as a “bite.” Mosquito bites often swell up hours after happening, causing a red ringed white bump about a centimeter in diameter. This bump can itch for days and over-scratching the bite can cause it to bleed. Mosquito bites can transmit diseases, such as malaria and West Nile Virus, so authorities in many areas take measures to reduce mosquito populations through pesticides or more organic means. An easy way to reduce mosquito populations in a residential area is the removal of standing water (where mosquitoes breed), and the use of repellents, such as DEET.