Mosquito & Fly Information



Phylum, Arthropoda; Class, Insecta; Order, Diptera

Identifying Features:

Appearance (Morphology)

•Eggs of some mosquitoes float on the water in rafts.

•Larvae, often called wigglers, have a soft body, a hard head and a breathing tube, or siphon, at the tip of the abdomen.

•Pupae are shaped like a comma, and are commonly called tumblers or pups.

•Adults have delicate legs, a long proboscis and one pair of transparent wings.

Adult Males and Females:

Female mosquitoes are usually larger than males. Females have fine threadlike antennae with few hairs, whereas males have bushy antennae. Only Females bite.

Immature (different stages)

Mosquitoes are holometabolous insects and therefore grow through an egg, larva, pupa to adult stage. The larvae and pupae are aquatic, the adults are free flying. At 80° F the larva goes through four larval instars in about 4 days before pupating. The pupa takes three days before the adult emerges. Adult females live several weeks if given a source of sugar. Males usually live less than a week.

Natural History:


Larvae eat many things. They graze over rocks and plant material removing growing algae and bacteria. They will filter feed from polluted water, but the water in which they live must never be allowed to develop a scum as they must be able to contact the air through the siphon at the end of the abdomen. Both male and female adults feed on nectar. Females also feed on blood which is needed to produce eggs. Some species can produce eggs without a blood meal. Males do not feed on blood.


Larvae and pupae live in water, usually still water. They do not survive well in rushing streams or badly polluted water. Adults hide in vegetation near water or in cool, damp places. Many species fly in search of blood meals in the evening.


Many fish and predatory aquatic insects eat larvae and pupae. Bats, birds and spiders eat flying adults.

Interesting Behaviors

Watching the feeding behavior of larvae is instructive. Larvae are such effective filter feeders that they can clean polluted water. Adult females respond to cues produced by warm-blooded animals.

Impacts on the Ecosystem

Positive: Mosquito larvae are important food for fish and other predatory aquatic animals. Adult mosquitoes are also important food for birds, bats and other arthropods, including dragonflies and spiders.

Negative: Mosquitoes transmit pathogens that cause some of the worst diseases known, including malaria, yellow fever, dengue fever and encephalitis. However, mosquitoes only transmit the pathogens. In most cases, they must feed on someone with the disease to be able to transmit it to another person. Adult mosquitoes reared from larvae collected from ponds seldom carry pathogens. Do not let field-caught mosquitoes feed on your hand.

Further and more-detailed mosquito information may be found at:



Phylum, Arthropoda; Class, Insecta; Order, Diptera; Family, Simuliidae.

The typical lifespan of Black Flies is between 2-3 weeks. Black Flies breed typically in clear running water. Females lay anywhere from 150-500 eggs. Black Flies don’t lay their eggs in polluted water like mosquitoes. Black Flies reproduce anywhere from 1 to 6 generations in a year. Of course it all depends on Vermont’s climate and temperature and of course the Black Fly species.