Orders
Objectives
After Insect you have completed this unit you should know for each order:
its common name, order name, and meaning of the order name
its development, or metamorphosis
3-4 facts regarding its life history and/or economic importance
its wing type, leg types and mouth adaptations
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Question
2
Introduction
The answer to the question, "What is the difference
between a bee and a beetle?" may seem easy. But
when you really think about it, it is a challenge to
describe the difference to another person. They both
have wings, six legs, and antennae. You can't just
say, "Well, that looks like a bee and that looks like a
beetle." There is more to it than that. By the end of this
unit you should be able to tell someone without
hesitation the difference between these two insects as
well as many others.
How do you tell the
difference between
a bee and a beetle?
scarab beetle
As you progress through the unit, you will refer to the
textbook for information to fill in your study guide table.
The textbook has a appendix dedicated to describing
the insect orders, but more detailed descriptions are
scattered in textboxes throughout chapters 7-14.
honey bees
3
Classification Review
4
Classification Review Diagram
You should recall from previous units how organisms are organized. An
organism is first classified into a Kingdom (such as Animalia, Plantae,
Fungi, etc), then Phylum, Class, Order, Family and lastly Genus and
species. You have already learned that Insects are in the kingdom
Animalia and the phylum Arthropoda along with lobsters, spiders and
crabs. You also know that insects are in a separate class called
Insecta. The class Insecta is then broken down into 30 insect orders
and these orders are then separated into families. For example, a
scarab beetle is in the class Insecta, the order Coleoptera and the family
Scarabaeidae. A bee is in the class Insecta, the order Hymenoptera,
and the family Apidae. This lineage is diagramed on the next slide.
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6
Review Terms
Review Terms: Answers
This unit will familiarize you with some of the major insect
orders. Before you get started, see how many of these
terms you know by writing their definitions on a piece of
paper. These terms will help you throughout the unit and
on your lab projects.
1. Anamorphic:
2. Ametabolous:
3. Hemimetabolous:
4. Holometabolous:
5. Apterygote:
6. Paleopterous:
7. Pterygote:
8. Neoptera:
9. Exopterygote:
10. Endopterygote:
Anamorphic: Development in some
parainsects where abdominal segments
are added during the molting process.
Ametabolous: An insect that undergoes
slight or no metamorphosis. The young
look just like the adult. They also keep
molting even after becoming an adult,
something the other kinds of insects
don't do.
Hemimetabolous: An insect that
undergoes incomplete metamorphosis.
The young look very similar to the
adult.
Cuckoo wasp
7
Review Terms Answers Continued
Holometabolous: An insect that
undergoes complete metamorphosis.
This type of metamorphosis includes
the larval stage, pupal stage and adult
stage.
Ametabolous
egg
juvenile
adult
Hemimetabolous
egg
juvenile
adult
Holometabolous
egg
larva
pupa
adult
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Hexapoda
Apterygote: An insect that doesn't have wings.
Paleopterous: Insects having wings, but the wings cannot fold back over the insect's
abdomen.
Pterygote: This term refers to all winged insects.
Neoptera: Having wings, but the wings have a flexon, or hinge, that allows the wing
to be folded back over the abdomen.
Exopterygote: Insects with wings that develop from structures called wing pads
located on the outside of the growing insect.
Endopterygote: Insects with wings that develop from internal wing pads present in
the larvae.
I hope you enjoy learning about the insect
orders. Before we get started, I want to introduce you to
several taxonomic groupings. Some scientists like to group
things together and others like to split them. Over the next few
slides, we will look at two classification schemes, one that
lumps groups into three classes and one that splits them into
four. Be sure to read chapter 7 in the text to see how these
schemes are derived.
9
Read textbook pages 178-183.
10
vespid wasp
Four Class Scheme
Hexapoda Continued
These lines indicate relatedness. It is like a family tree.
All six-legged arthropods, hexapods, were once classified in
the Class Insecta. After some debate, some scientists group
hexapods into three classes, Parainsecta, Entognatha, and
Insecta and some scientists split them into four classes,
Protura, Collembola, Diplura and Insecta. Each of the
classification schemes are based on certain similarities
between the groups. We will take a look at two cladograms
that show the differing opinions of how these organisms
should be classified.
Gullen and Cranston, 2005, pg 182
Note: Because the parainsects are so closely related to the insects, we still consider
them insects in the non-technical sense of the term and encourage you to include
them in your insect collection.
Read textbook page 181.
11
In this cladogram, the proturans, collembolens, diplurans and insects
are all considered to be separate classes. We will study each of these
groups individually, but here, you can follow the lines to see how the
classes are all related. The complete cladogram is on page 182 of your
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text.
Three Class Scheme
Objectives Recap
These lines indicate relatedness.
It is like a family tree.
With those terms and ideas firmly established in your mind you are now
ready to learn about the insect orders. There are 30 insect orders in the
current classification scheme. We wont be able to cover some of the
lesser known orders in this lecture, but you can read about them in the
text if you wish. You will read about each of the more common orders in
the lecture and text and will complete the chart on your study guide. Just
as a reminder, after you have completed this unit you should know for
each order:
Daly et. al, 1998, pg.306-307
This is another example of a cladogram showing relatedness between groups. You
can see that the proturans and collembolens are together in the class Parainsecta
and the diplurans have been separated into the class Entognatha. Well start by
learning about these more ancient groups. We will begin with the proturans and
collembolens, then move on to the diplurans and then into the wingless subclass of
Insecta, the apterygotes. Note that these cladograms are proposed relationships
that are based on current morphological and genetic data. As new technology
becomes available relationships between the groups can change to reflect new 13
information.
1. its common name
2. its development, or metamorphosis
3. 2-3 facts regarding its life history and/or
economic importance
4. any special adaptations of mouthparts, legs,
or wings
5. the meaning of the order name
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thrips
first tail
Class Parainsecta: Order Protura
Proturan Walking Video
Proturans are eyeless and lack
antennae. They are very small, less
than 2 mm, and they undergo
anamorphic development. The nymphs
begin with nine segments, but an adult
has twelve. The forelegs are enlarged
and serve as sensory organs (like
antennae). They do not have tentoria
or cerci. The legs are five segmented.
proturan
Read textbook page 183 and 231.
Notice the meaning of the order name in the top right corner.
15
16
glue wedge
Proturan Defensive Posture Video
Class Parainsecta: Order Collembola
This is another organism that is
not a part of the class Insecta.
Collembolans are tiny arthropods
that live in the soil where they
feed on fungi and decaying
vegetation. Thus, they are
important decomposers in the
ecosystem. They are often called
springtails" because they can
tuck their tail (furcula) underneath
them-- similar to cocking a gun-and can snap it back out
"springing" them off of the
ground.
collembolan
Read textbook pages 183, 230 and 231.
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Fill out the table on your study guide under the heading "Insect Orders."
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two tail
Class Entognatha: Order Diplura
Entognathans are a group that have
enclosed mandibles. Diplurans are a
part of this group. Diplurans are soil
arthropods and have over 700
described species. They are eyeless,
but do have antennae. Their name
comes from the fact that they have
two sclerotized forceps on the end of
the abdomen. The size ranges from
0.5-50mm in length. Some diplurans
feed on vegetation while others are
predaceous. These guys have 10
body segments and continue to molt
throughout their life.
silverfish
Thysanurans include silverfish and firebrats. Silverfish are a typical
example of insects with ametabolous development. You have probably
seen these primitive insects in your bathroom. They are wingless, have
silver scales, compound eyes and three caudal filaments. These guys
are soft bodied and need to be preserved in alcohol. They are
occasional invaders of homes and prefer moist environments.
http://www.earthlife.net/insects/diplura.html
dipluran
Notice that the ending
-ura means tail.
bristle tail
Class Insecta: Subclass Apterygota:
Order Thysanura (Zygentoma)
Read textbook pages 183-184, 231.
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Note: You will notice that your text includes silverfish in the order Zygentoma.
Many other entomological texts have silverfish in the order Thysanura. Either
term is acceptable. I will refer to them as Thysanurans as we go throughout the
lecture.
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Read textbook pages 185 and 232.
Class Insecta: Subclass Pterygota:
Order Ephemeroptera (Mayflies)
Primitive Pterygotes
Daly et. al, 1998, pg 306-307
Gullen and Cranston, 2005, pg 182
The next group we will consider are the primitive pterygotes. These
insects were the first to develop wings. These wings cannot fold and must
be held out away from the body. The Infraclass is Paleoptera which
means ancient winged
ephemera - short-lived
Mayfly naiads live in water-- usually
under rocks. They are herbivorous and
are good indicators of water quality.
The nymphs have abdominal gills and
three caudal filaments. When they go
through metamorphosis they will go
through a subimago stage and then molt
into an adult mayfly like the one pictured
to the left. The triangular wings held
together over the body and the three
mayfly
caudal filaments are two identifying
We are now entering the division characteristics. Ephemeropterans like
of the winged insects. Notice that their ephemeral namesake, are short
the name often ends in -ptera
lived. The adults emerge, mate and die
which means wing.
not even taking time to eat.
Note: a naiad is an aquatic nymph of a hemimetabolous insect.
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22
Read textbook pages 185 and 252.
Class Insecta: Subclass Pterygota:
Order Odonata (Damselflies, Dragonflies)
toothed ones
Odonates, like the mayflies you just read about, also
have aquatic immatures. Dragonfly and damselfly
naiads are easy to distinguish from one another.
Damselfly nymphs have three caudal gills that are
absent on dragonfly nymphs. The gills on the
damselfly larvae are articulated and easily break off
when the animal is disturbed.
Order Odonata (Damselflies, Dragonflies) continued
toothed ones
compound eyes
damselfly
dragonfly
The damselfly adult has a delicate looking body. The
adult holds its wings together above the abdomen.
They are considered good luck and make a heart
shape when they mate. Take a look around next time
you are collecting near a pond or lake. Dragonfly
adults have a robust body that with the outstretched
wings, resembles an airplane. They both have large
compound eyes that aid them in capturing prey.
These guys are predators in both the immature and
adult forms.
Can you tell which is which? Remember,
the damselfly larva has gills.
23
Read textbook pages 186 and 253-254.
Read textbook pages 186 and 253-254.
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Infraclass Neoptera: Division Exopterygota
Neopteran Phylogeny
Wing pads
Daly et. al, 1998, pg 306
Gullen and Cranston, 2005, pg 182
predatory hemipterans
In unit two we discussed the development of neopterous wings. If you remember
from that discussion, neopterous wings are foldable. The classification of
neopterous insect orders, as with the insect classes, is open for some debate.
Before we move on, please read about this debate in the Division Neoptera section
on page 186.
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Read textbook page 186.
Order Blattodea
(Cockroaches)
In one classification scheme, a division of the Infraclass Neoptera is Exoterygota.
Exopterygotes develop their wings on the outside of the body. These wings are
seen as wing pads on the developing nymph. You can see which orders are included
from the cladogram above. We will now review these orders individually.
Note: These wing pads are an indication that the insect has not developed into the
adult stage. This is a tip you can use while you are out collecting your insects.
Mantis is the Greek word for Mantids
Blatta is the Greek word for cockroach
Okay, one of the first exopterygotes we are going to
cover is one of my favorites cockroaches.
Cockroaches are natures cleanup crew, but most
people consider them to be nothing but pests. While
there are a few pest species, there are many more
non-pest species (about 4000 to be exact). In fact,
cockroaches have contributed much to science from
everything from anatomy to neurology. Cockroaches
are dorso-ventrally flattened and are well adapted to
their environment. The pronotum is designed to
Florida woods cockroach and egg case
protect its head and their cursorial legs are for
running. Cockroaches have many nicknames such as
palmetto, water, or croton bug. Like most insects,
they come in a variety of shapes and sizes. Although
they are hemimetabolous and exopterygotes, some
adults lack wings.
Australian cockroach
Order Mantodea
(Praying Mantids)
Mantids are known for their legs that
have the ability to strike and catch
prey quickly. These raptorial legs
have spines that help the predator to
hold onto its prey while its chewing
mouthparts dig in.
Mantids are the only insects that have
the ability to rotate head to look over
their shoulder. This allows them to
spot prey and prepare for a quick grab
without moving their body. Mantids
have styrofoam like egg cases and are
hemimetabolous.
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Cuban cockroach
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equal wings
Greek for Mantid and Phantom
Order Isoptera (Termites)
Termites are also known as white ants. They are
the only hemimetabolous insect with true social
behavior. These insects have a caste system
that includes workers, soldiers, and
reproductives. The worker is the bread winner of
the family. They are nearly blind and they forage
soldier termites
for food by building tunnels to protect
themselves. The workers are charged with
protecting the colony. They have a larger head
than the common workers and large strong
mandibles. There is about one soldier for every
100 workers in subterranean termite colonies.
Reproductives are the only termites that have
wings which they lose soon after finding mate
and a new place to nest. Termite colonies consist
of both males and females and the king remains
termite reproductive
with the queen in the colony.
Note: Believe it or not, termites are closely related to cockroaches.
This is an order that is only found in Africa. Why then should we mention it?
This order, thought to be extinct, was recently found living in South and
Eastern Africa. Species in this hemimetabolous order are still being named
and described. The media blitzed this discovery of such a strange critter.
Read more about this find on pages 189 and 349.
For more information, click on
attachments above and read the
Gladiators article from Scientific
American.
praying mantis
Read textbook pages 186 and 348.
Read textbook pages 188 and 236.
Order Mantophasmatodea
(Heel Walkers or Gladiators)
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Gullan and Cranston 2005, pg 501
Read pages textbook 189 and 349.
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Read textbook pages 188 and 326.
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Order Dermaptera
(Earwigs)
You can tell that you have now entered the
section of neopterous insects. As you can
see, the wings are folded on top of each
other over the abdomen and are not held
out to the side or straight back.
Cricket
Orthopterans are an important group of
plant feeding insects. The hind legs of
many orthopterans are modified into
saltitorial legs which are designed for
jumping and many have modifications for
making sound. The front wings are
thickened to protect the membranous fanlike wings underneath. These guys are
hemimetabolous and have chewing
mouthparts.
A mole cricket with
fossorial front legs.
A large lubber grasshopper
with coloring that tells
predators it's nasty to eat.
skin wing
straight wing
Order Orthoptera
(Grasshoppers, Crickets)
Read textbook pages 189 and 289.
Believe it or not; this earwig has wings.
The wings of adult earwigs are just
folded and packed away under small
leathery covers. Earwigs got their
name from the myth that earwigs enter
the ears of sleeping humans. Although
they look fierce, the abdominal pincers
wont hurt. They use these modified
cerci for grooming and defense. These
guys live in moist mulch and may be
found in rotting logs, or damp places
indoors. They are generalist feeders
and some species, usually wingless
ones, are predatory. Earwigs are
hemimetabolous and the immatures
are wingless.
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earwig
From the Greek phasm or phantom
Read textbook pages 190 and 290.
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uniform or same wings
(Cicadas, Leafhoppers, aphids, whiteflies, scales, etc.)
Homopterans differ from hemipterans by
uniformity of their wings and the origin of their
piercing-sucking mouthparts. Homopteran
forewings have a uniform texture unlike the halfwings of their hemipteran brothers and the
winged homopterans hold their wings in a tent
shape over their bodies. The proboscis is
cicada
opistognathous meaning that it is on the ventral
posterior margin of the head capsule. The
proboscis, or beak, is smaller in homopterans
and they use this beak to suck out juices from
spittlebug
vascular plants.
A common representative of this suborder is the
cicada. Many of you probably collected the
cicada shells as a child. The nymph lives
spittlebug immature
underground for as many as seventeen years
feeding on roots of trees before it emerges as an
adult. On the next slide, you will see some other
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Read textbook pages 192,
homopteran representatives.
292 and 259.
This order is split into two subborders,
the Heteroptera and the Homoptera.
The Homoptera suborder used to be its
own order, but now it is commonly
lumped under the Order
Hemiptera. Hemipterans are the true
Chinch Bug
bugs. They have leathery fore wings and
Wheel Bug
membranous hind wings. The leathery
forewings are halved with the hind end
being membraneous (see red outline on
the right). Behind the pronotum is a
triangular shield (see the yellow outline to
the right). The top right side of this
scutellum is where you will pin the insect
for your collection. The mouths of
hemipterans are adapted for the piercing
and sucking of plant or animal juices
A common stink bug.
(Notice the red rostrum on the wheel bug).
Some hemipterans have scent glands, and
34
Read textbook pages
some may transmit disease.
192, 292 and 259.
Suborder Homoptera Continued
uniform or same wings
(Cicadas, Leafhoppers, aphids, whiteflies, scales, etc.)
scale insect
whiteflies
aphids
treehopper
The digestive system of most homopterans has a filtering system.
This allows the insect to ingest large amounts of sap and then excrete the excess
water and sugars. Ants appreciate this meal of honeydew and provide protection
to the insects in exchange for this sweet meal. Many homopterans, like aphids
and leaf hoppers, are important carriers of plant diseases. Others are beneficial,
like the lac scale that produces shellac and the cochineal
insect that produces red dye.
www.craftsmidwales.co.uk/
scarf2.jpg
Florida walking stick
Suborder Homoptera
half wings
Order Hemiptera: Suborder Heteroptera (True Bugs)
Order Phasmatodea (Walking sticks)
Insects in this order look like twigs or
branches. The males are often
smaller than the females as seen in
this picture of a mating pair of Florida
Walking Sticks with the smaller male
on the back of the female. These
guys move slowly and often will sway
like a branch in the wind. A few
species have wings, but most are
brachypterous meaning they have
reduced wings. Walking sticks can
have some interesting ornamentation
are a favorite in insect zoos. The
largest insect can reach 12 inches
long.
32
Read textbook pages 190 and 235.
Scarf dyed with cochineal dye
Read textbook pages 2-3.
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fringe wing
Order Thysanoptera (Thrips)
Some thrips are common pests of plants. They
inject their mouthparts and suck the plant juices of
the buds, flowers or fruits of the plant causing
damage to these structures. Sometimes if you pick
a plant and pull it apart you will see tiny wormylooking thrips crawling on your hand. These guys
have rasping mouthparts and have been known to
try rasping humans for a meal. Some species are
predaceous and feed on mites. Adults can be
winged or wingless. The wings are thin and are
covered with a fringe of hairs. Thirps are
hemimetabolous, but they may have a pseudo
pupal stage with a silken cocoon. This puzzles
scientists and may be an instance of convergent
evolution.
Lice are wingless parasites of birds and mammals. There are two suborders of
lice, Anoplura the sucking lice, and Mallophaga the biting lice. Anoplurans
are small and have a flat body. They have only one claw and a single tarsal
segment and are mainly a pest of mammals. Mallophagans are mainly a pest of
birds where they feed on feathers and skin debris. They have a larger head and two
claws on each of two tarsal segments. These lice are pretty host specific and may be
limited to feeding on a specific species. Lice are ectoparasites and need to remain
close to the host. Therefore, they attach their eggs, or nits, to the hair or feathers of
the host.
thrips
A chewing louse, a
common pest of birds.
NOTE: The term thrips is used both as the singular and plural form!
Read textbook pages 191 and 291.
37
Daly et. al, 1998, pg 306-307
Gullen and Cranston, 2005, pg 182
If you remember from unit two, the fourth stage of insect evolution was neopterous
with holometabolous development. Well, Endopterygota is composed of insects with
that description. They have a wingless larval stage that looks different from the adult.
As with most of the groups, there is some debate here too. Please read page 193
under the heading Entopterygota.
Read textbook pages 193-194.
stable fly
If you notice the names, you will see that if the word fly is separated,
then it is a Dipteran. If it is attached, it is not. Example: House fly or Butterfly
head lice nits
Biting lice usually dont transmit disease, but sucking lice have been proven to
transmit, relapsing fever (Borellia recurrentis), epidemic typhus (Rickettsia
prowazeki), and trench fever (Rickettsia quintana). Trench fever was common
in WWI and was a factor in the collapse of the Russian army.
38
Read textbook pages 191 and 389 .
A carrion beetle.
CSI anyone?
39
two wings
Order Diptera (True Flies)
A sucking louse on a
human's skin.
sheath wing
Order Coleoptera (Beetles)
Infraclass Neoptera: Division Endopterygota
Dipterans are the true flies. They have one set
of functional forewings and the hind wings have been
modified into halteres which function as a gyroscope
helping to maintain balance. Flies are holometabolous
and the larvae are known as maggots. Maggots are soft
bodied and live in moist environments where they
wont desiccate. Flies have many mouth
adaptations. Most are haustellate and are
liquid feeders. Some flies, like mosquitoes,
have piercing-sucking mouthparts, while
others, like house flies have sponging and
some, like horse flies have lapping
bee fly
mouthparts. Flies are important in several
ways, some are efficient pollinators,
some damage crops and some spread disease.
wingless louse
Order Phthiraptera (Lice)
Coleoptera is the largest order of
insects (about 40% of all known
animals). These guys are
holometabolous and the larvae are
referred to as grubs. The front wings in
beetles are as hard as the rest of the
exoskeleton and serve to protect the
membranous hind wings that are used
for flight. Beetles feed on a variety of
foods including everything from plants
to fungus, to rotting meat, poop, and
blood. Beetles have various
modifications of the pronotum,
mandibles and antennae that you will
read about.
Wow! What a pile of dung.
Can you believe the
Egyptians worshiped this beetle?
Read textbook pages 194-195,
295-296 and 259.
tiger beetle a quick predator
A scarab beetle with flared
antennae to catch the scent
of a mate or food.
A firefly or lightning bug.
Of course this is neither
a fly or a bug, but a beetle.
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membrane wing
Order Hymenoptera (bees, ants, and wasps)
mosquito
love bugs
horse fly
41
Read textbook pages 196, 257, and 391-392.
Hymenopterans are social insects that are specialized for
their particular niche. They are holometabolous and have
mandibulate mouthparts (some, like bees have
modifications where their mouth is shaped like a tongue
to lap nectar from flowers). They have four wings that
parasitic wasp
are joined together (fore and hind) by tiny hooks called
hamuli. Some wasps are herbivores and form galls,
others are tiny and are parasites of other insects. Many
bees and wasps are important pollinators of plants. As
the bee lands on a flower to suck its sweet nectar for
food, it catches pollen on its body. When it lands on
another flower, this pollen will fall off thereby fertilizing the
bee pollinating a flower
flower. Ants are common pests around homes. Those of
you in the Southeastern US, are familiar with fire ants.
These were accidentally introduced into the US in the
1930s and have been quite successful. An interesting
fact about hymenopterans is that females develop from
fertilized eggs and males develop from unfertilized eggs.
Cool huh?
ant
Read textbook pages 197 and 325. 42
Order Lepidoptera (Butterflies and Moths)
scale wing
Moth and Butterfly differences
Lepidoptera is the second largest order of insects behind Coleoptera.
Lepidopterans are holometabolous and the larvae are known as caterpillars.
While it appears that caterpillars have many legs, there are only three
true pair and 2-8 pair of fleshy prolegs. Most caterpillars are herbivorous
and many can cause substantial damage to crops trees, or ornamental plants.
Some caterpillars can sting because they are covered with urdicating hairs.
Adult leps are well known for their scaled wings. A common site at gardens
and zoos is a butterfly garden. The adult butterflies and moths feed by a siphoning
tube that is coiled up for storage.
Moths
the antennae taper to a point
they are thick bodied
the wings lay against the
abdomen at rest
Sphinx moth
Butterflies
the antennae end in a club
the body is more delicate
the wings are held upright or
out to the side at rest
brushfooted butterfly
UF - Butler
hair wing
Order Trichoptera (Caddisflies)
Trichopterans are often mistaken for
moths. They are related, but have some
differences. They have long filiform
antennae and hold their wings roof-like
over their body. The wings are fringed with
a row of hairs along the edge. These guys
are holometabolous and the immatures are
aquatic. They look like caterpillars and
some make nets or cases to live in. The
cases are made from pebbles in the
environment, so jewelry makers have
discovered they can add colored beads or
pebbles to the larval habitat and have the
caddisflies make them custom jewelry.
43
Caddisfly adult
http://www.wildscape.com/jewelry/
Dingy purplewing with curled proboscis
Read textbook pages 198-199
and 296-297.
Caddisfly larval
case earrings
44
Monarch caterpillar and adult
wingless tube
Order Siphonaptera (fleas)
Fleas are laterally flattened and are secondarily wingless, meaning that they
once had wings. All adults are blood feeders, hematophagous,
and have piercing-sucking mouthparts. The hind legs are saltorial. Fleas are
holometabolous with wormlike larvae that live off of the fecal material of the
adults. The pupae reside in a cocoon made up of environmental debris. This
makes home infestations difficult since the pupae may blend in with the carpet.
There are over 2400 species of fleas with 3/4 of them being affiliated with
rodents. Fleas are medically important not just because of their irritating bites,
but because they are disease vectors. They have even been known to change
history.
Oriental Rat Flea: Plague vector
The bubonic plague was the most common form of the
Black Death. Septicemic plague is the most rare form.
The mortality was close to 100% (even today there is no
treatment). Symptoms are a high fever and skin turning
deep shades of purple due to disseminated intravascular
coagulation. Yes, all from a flea bite.
flea
Read textbook pages 196 and 390.
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Read textbook pages 198 and 255-256.
large wings
nerve wing
Order Neuroptera (Lacewings, Antlions, etc.)
Neuropterans are holometabolous
insects that are generally considered
to be beneficial. For example, the
larva and adults of lacewings feed on
aphids and other small insects. You
can purchase lacewing eggs or larva
and release them in a garden or
greenhouse to control insect pests. brown lacewing
Another fun neuropteran is the
antlion. Antlion larvae, also known as
doodle bugs, are fascinating
creatures. They dig pits in the sand
and wait at the bottom for others
insects (like ants) to get trapped.
Neuropterans are generally weak
lacewing eggs
fliers.
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Order Megaloptera (dobsonflies)
Another order closely related to the neuropterans is the dobsonfly.
The aquatic larva, often called hellgrammites, are often used as fish bait.
The males have very large mandibles.
green lacewing
dobsonfly
male dobsonfly
Order Plecoptera: (stoneflies)
antlion adult
Note: The text lumps all Neuropterida together. This group includes the orders,
Megaloptera, Raphidioptera, and Neuroptera.
Read textbook pages 195 and
For a bit of neuropteran fun, visit
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http://www.antlionfarms.com/videos___pics.
350-351.
Read textbook pages 195 and
350-351.
folded wing
Stoneflies are another insect with aquatic nymphs.
The adults emerge at the same time and live for only
a few weeks.
Read textbook pages 187 and 255.
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Review
Conclusion
Your mind is probably spinning with all the terms and the characteristics of
each order. Do you know the difference between a bee and a beetle
yet? How many wings does a fly have? During an upcoming lab or in your
own collection, you should be able to look at specimens and the differences
will become clearer to you. Now that you
know the order characteristics, you will
be an expert in no time.
In review, the insect orders are grouped
according to whether or not they are
ametabolous, hemimetabolous or
holometabolous. You will also see that the
insect orders are grouped according to the
absence or presence of wings and whether or
not the wing has a flexon, i.e. apterygote,
paleopterous or neopterous. The orders are
also grouped according to how the wings
develop. If the wings develop from structures
on the outside of the body the insect is called
an exopterygote. If the wings develop from
internal wing pads, the insect is called an
endopterygote. Be sure you know which
orders go with each classification.
wingless wasp cow killer ant
Note: To review the order characteristics and check your chart from the
study guide, you may refer to the appendix, A Reference Guide to Orders,
on pages 499-505.
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