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    Mosquito Biology

    The field of mosquito biology is extremely vast and variable, so please realize that some things in this section may not apply to all mosquito species. Mosquitoes are an order of insects - Diptera - the flies. All flies are holometabolous meaning they have a complete life cycle and their immature forms are very different from the adult forms. In the case of immature mosquitoes (larvae), they are aquatic (living in water), whereas the adults are terrestrial (living on land). There are approximately 85 recorded species of mosquitoes in the state of Texas and their behavior and habitats vary by species. Some mosquitoes will spend their winters as eggs in soil or in containers, while others will hibernate (diapause) or go through a period of inactivity (quiescence). 

    Eggs- Mosquitoes lay eggs, either singly (as in the case with many Aedes mosquitoes) or in rafts (as in the case with many Culex mosquitoes). These eggs are sometimes laid in soil and tree rot holes and hatch when these environments fill up with water, or are laid directly on the surface of stagnant water. When water is present, eggs usually hatch within a few hours or up to a couple of days.

    Larvae- Larvae (larva) are also knows as “wigglers” or” wrigglers”. They almost appear like tiny little worm-like creatures found in water. They swim by moving their bodies back and forth and must breathe through ‘siphons’, a breathing apparatus that allows them to access air at the surface of the water. Larvae can be less than 1 mm in length and commonly up to 8 mm for more mature larvae. Larvae go through four life stages called “instars” in which they must molt or shed their skin in order to get bigger. In the late portion of their fourth instar, they discontinue feeding and prepare to enter the next stage of life. Each instar takes approximately two days complete.

    Pupae- Pupae (pupa) are also known as “tumblers” which describes their swimming motion in which they seem to complete somersaults. No feeding takes place in this stage and there is not much activity. They are developing adult appendages such as wings, legs, compound eyes and adult mouthparts. This stage usually takes one to two days.

    Emergence - When pupal development is complete, the pupal shell (exuvia) splits open and the adult mosquito steps onto the surface of the water. Here the exoskeleton (hard outer shell) must harden. This process is known as sclerotinization and is complete in about two to three hours.

    Adult- Adult mosquito behaviors vary by species. Only the adult females will take blood meals to be able to support egg production. Plant nectar serves as a main source of energy for all mosquitoes. Male mosquitoes typically live from one to two weeks and their sole purpose is to breed. Females of some species can live up to six months in times of overwintering, but typically many females will live about six weeks. Some mosquito species will have one particular host such as only a bird, only a mammal or even only reptiles or amphibians while as others are generalist (feeding on almost any animal).