Mosquitos
Adult Males and Females
Female mosquitoes are usually larger than males. Females have fine threadlike antennae with few hairs, whereas males have bushy antennae. Eggs of some mosquitoes float on the water in rafts. Adults have delicate legs, a long proboscis and one pair of transparent wings.
Immature's (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
Food
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.
Habitat
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.
Predators
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.
Impact 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.
Excerpt from a paper contained in the Center for Insect
Science Education Outreach. The University of Arizona
Flies, The Indoor and Outdoor Nuisance
Adult Males and Females
Males and females are hard to distinguish. Females are usually larger and
can extend the tip of the abdomen to form an ovipositor which is used to
lay eggs. Sometimes males have enlarged eyes which meet on top of the head.
Immature's (different
stages)
Flies are holometabolous, therefore they have four distinct morphological
stages; egg, larva (maggot), pupa and adult. After hatching from the egg,
larvae molt twice as they grow. Molting of maggots is difficult to see.
Larvae are maggots with a legless soft body except for the dark mouth hooks.
Pupae are dark, and look like a small barrel.
Natural History
Food
Larvae feed on decaying meat and feces. Adult flies feed on sugary food
of any kind, including nectar and rotting fruit.
Habitat
Flies live in garbage and wherever animal feces are available. Dead animals
attract flies within hours after death. Most flies are diurnal.
Predators
Many birds, bats, spiders, and insects such as dragonflies eat the adults.
Predatory and parasitic insects eat the larvae.
Interesting Behaviors
- The eyes of flies are among the most complex in the insect world.
They are compound eyes with many individual facets, each representing
a separate light-detecting unit. The light reflected from the eye
of a horsefly can form a rainbow.
- Flies taste, smell, and feel with the hairs that cover their bodies.
The hairs on the fly's mouth parts and feet are used for tasting.
Flies taste what they walk on. If they walk onto something tasty,
they put down their mouth and taste it again.
- Flies use other hairs to tell them when they touch something.
These hairs bend when touched.
- The eyes of a fly do not have eyelids, so flies rub their eyes
with their feet to keep them clean.
A fly cleans itself constantly.
- Flies walk on smooth surfaces using sticky soft pads that act
like glue. This allows them to walk on vertical glass surfaces and
upside down.
- Impact on the Ecosystem
Positive
Flies and other insects, such as burying beetles, are very important
in consuming and eliminating dead bodies of animals. Flies are also
essential in the conversion of feces and decaying vegetation to soil.
Flies serve as prey to many other animals. Some flies aid in pollination.
Negative
Because of their habits of being attracted to feces and decaying meat,
flies have been implicated in transmission of disease such as dysentery,
typhoid fever, and cholera.
Excerpt from a paper contained in the Center for Insect Science
Education Outreach. The University of Arizona |
