The Bad and
Grade Level: Late Elementary
Insects: The Good, The Bad and the Unusual
Created by Deborah Y. Richardson
with assistance from Cheryl Toefield-Keen
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Entomology: enAtoAmolAoAgy a branch of zoology that deals with insects The Greek
word entomon, meaning “notched,” refers to the segmented body plan of the insect.
How many different kinds of insects are there?
There are over a million species of insects. There are over 90,000 spp. of insects in North America. Insects
outnumber all other animals at a rate of 4 to 1.
What was the biggest insect ever?
The fossil dragonfly, Meganeura, that lived about 250 million years ago was probably the largest insect
ever. Its wingspan was over two feet.
What is the largest living insect?
LONGEST - a tropical stick insect - 13 inches from end to end.
HEAVIEST - the goliath beetle in Africa (weighs 1/4 pound and is 5 inches long). They belong to the same
family (scarab beetles) as the eastern hercules beetle, which is about 2 inches long including the horn.
What is the smallest insect?
The smallest insects are fairyflies, which are insects that parasitize or lay their eggs inside other insects'
eggs (including pest insects!). Fairyflies are only 1/5 of a millimeter long.
How fast can insects fly?
The male deer bot fly is reputed to develop flying speeds of several hundred miles per hour, but this is
probably an exaggeration. A tabanid fly, related to horse flies, has been clocked at 90 miles per hour. Hawk
moths have been timed at 33.5 miles per hour. A dragonfly of the species Anax parthenope has been
clocked at almost 18 miles per hour. Honeybees fly at about 7 miles per hour, and have to beat their wings
190 times per second to do it.
How fast can insects flap their wings?
Insects with the fastest wing beat frequency are the no-see-ums, or very tiny midges, which beat their hairy
wings 1,046 times per second. Male mosquitoes beat their wings 450 to 600 times per second.
Cabbageworm butterflies beat their wings nine times per second.
Is a spider an insect?
Spiders are arachnids. They eat insects.
There are many kinds of insects. All insects have:
3 body parts
3 or 4 life stages
Some insects have one or two pairs of wings.
Spiders are different from insects. Spiders have:
2 body parts
3 life stages
Insect body parts
The most visible parts of the body of an adult insect are: the head, the antennae, the
mouthparts, the thorax, the wings, the legs, and the abdomen.
The head is the anterior (front) of the three body regions of an adult
insect. It has the eyes (usually a pair of compound eyes), the antennae and
Mouthparts: The mouthparts of adult insects can be of different types. Many species have
the chewing type, for example in grasshoppers and beetles. Others have sucking mouthparts
for example shaped like stylets (needle) in bugs and aphids or shaped like a coiled tongue in
butterflies and moths. The different types of mouthparts determine how the insect feeds.
Antennae: The head of most adult insects bears a pair of antennae. Insects use the antennae
to detect odors or they use them as tactile (touch) organs. Antennae are very variable in form
The thorax is the middle of the three body regions of an adult insect. It is
composed of 3 segments. It bears 3 pairs of legs (one on each segment) and
usually 2 pairs of wings. Some insects have only 1 pair of wings.
Thorax Legs: Adult insects have 6 legs. Each of the segments of the thorax bears 1 pair
of legs. The legs are segmented. Often the last segment of the leg bears a small claw. In
some insects, the legs are specially adapted for jumping.
Wings: Most adult insects have 2 pairs of wings, but some (for example flies) have only 1
pair of wings. Usually the wings are membranous but in some insects they can be leathery or
hard. Sometimes the wings bear hairs or small scales.
The abdomen is the posterior of the three body regions of an adult insect. It is
composed of 11 segments. The abdomen bears the external genitalia of the
insect. In female insects these consist of an ovipositor.
The most dangerous insects are mosquitoes, which
pass on West Nile Virus, a parasite causing malaria,
as well as the diseases dengue, yellow fever and
certain types of encephalitis. Malaria kills a million
people a year.
A bee has five eyes, two large compound eyes on either side of its head, and three
ocelli (primitive eyes) on top of its head to detect light intensity.
Honeybees fly at about 7 miles per hour, and have to beat their wings 190 times
per second to do it. A bumble bee flaps its wings 160 beats per second.
The first week as an adult worker, honeybees clean the hive. By the second week,
they feed the young. The third week, they make and repair wax cells in the hive.
By the fourth week, they have begun guarding the hive, and finally, they will visit
flowers for pollen (bees have built-in saddle bags) and nectar from the fifth week
till they die. Workers might live for 6 to 8 weeks, while queens live up to 5 years.
The total distance of the many trips honey bees travel to produce a pound of honey
is about equal to twice the distance around the world.
The buzzing of flies and bees is not produced by any sound-producing apparatus
This bee is an effective
within the insects' bodies. It is simply the sound of their wings moving up and
pollinator for blueberry
down at a rapid rate.
Honey bees air condition their hive when it gets hot - some of the workers position
themselves at the entrance to the hive and fan their wings. When it gets really hot they bring droplets of watered
down honey with them which cools the air even more.
Adult lady beetles and their larvae are an excellent, non-chemical way to
control aphids, Colorado potato beetles (egg stage) and other insect pests in
your garden Lady beetles, ladybugs, or ladybird beetles are among the most
visible and best known beneficial predatory insects. Over 450 species are
found in North America. Some are native and some have been introduced
from other countries.
Most lady beetles in North America are beneficial as both adults and larvae,
feeding primarily on aphids. They also feed on mites, small insects, and insect eggs. Many crops benefit
from lady beetles. They are helpful for growers of vegetables, grain crops, legumes, strawberries, and tree
crops; however any crop that is attacked by aphids will benefit from these beetles.
Female lady beetles may lay from 20 to more than 1,000 eggs over a one to three month period, commencing
in spring or early summer
A cockroach's heart is nothing but a simple tube with valves. The tube can pump blood
backwards and forwards in the insect. The heart can even stop moving, apparently
without harming the roach.
Cockroaches spread diseases like typhoid and dysentary. They can transmit bacteria
and iruses. Some people, especially those with asthma, are sensitive to the allergens
produced by these cockroaches. People are very upset when they find cockroaches in
their homes and kitchens.
The fastest runners are cockroaches, which can move almost a foot per second. However this only translates
to a little over 1 mph. Cockroaches have been on earth for over 300 million years.
Termites cause over $250 million in damages by eating wood. The queen of a termite
colony may lay 6,000 to 7,000 eggs per day, and may live 15 to 50 years.
Termites are the insects with the biggest nests. The largest termite mound, found in
Australia was 20 feet across the base. The tallest termite mound, found in Africa, was 42
feet high, however only 10 feet across. Some African and Australian termite colonies
may have as many as 3 million individuals.
The largest termite in the world is the African species Macrotermes bellicosus, which
reaches a length of 5 inches.
Soldier termites cannot feed themselves and must be fed by the workers
Common House Fly
The house fly is a common flying insect that is found throughout the world.
The house fly is often a carrier of diseases, such as typhoid fever, cholera, dysentery,
and anthrax. The fly transmits diseases by carrying disease organisms onto food. It
picks up disease organisms on its leg hairs or eats them and then regurgitates them onto
food (in the process of liquefying solid food).
A common housefly is faster--in one sense--than a jet airplane. The fly moves 300 times its body length in
one second, while the jet, at the speed of sound, travels 100 times its body length in one second. The average
house fly lives only two weeks. The compound eye of a housefly has more than 4,000 lenses A house fly
"hums" in the key of F and beats its wings over 20,000 beat a minute.
Rough Harvester Ant
Green Lacewing larva
Adult Squash bug