Download Insect-O-Rama_27Oct13

“Insect-O-Rama”
UGA Costa Rica
Compiled by Lindsay Stallcup
Updated October 27, 2013 by Katie Lutz and Mark Fisher
Contents:
Equipment needed
Length of workshop
Methods & equipment for collecting insects
Overview of insect ecology and morphology
Overview of common orders
Appendix: List of all insect orders
Working copy and CD with files
If you have questions, additions, or corrections,
please contact the Academic Program Coordinator
Insect-O-Rama – Page 1
Updated 27Oct2013
“Insect-O-Rama”
Equipment needed
Collecting equipment; nets (sweep nets for air and vegetation); aspirators; “beat stick”
Vials, containers, and plastic bags for collecting and sorting
Forceps, hand lenses, microscopes & lights
Approximate length of workshop
Introduction to workshop , ecology, morphology, and instructions for student collection: 20 minutes
Student collection of insects: 30-60 minutes (depending on group)
Overview of common orders: 30 minutes
Student sorting of insects and compilation of class collection: 30 minutes
Outline of Workshop
Part I. Insects – overview of ecology and morphology
A. Biodiversity in Costa Rica
B. Ecological roles of insects
C. What is an insect? Basic overview of taxonomy; characteristics shared by all insects
Part II. How do we collect insects?
A. Review methods for collecting insects (nets, aspirators, beat stick, black lights, pitfall traps)
B. Review different habitats in which students might collect insects (trails, forest, pasture, trees, bromeliads,
streams, ponds, at lights, etc.)
Part III. Students collect insects using nets, aspirators, etc.
A. Distribute nets, aspirators, vials, containers, etc.
B. Send students into field for 30-60 minutes of collection (instructor decides how long). It may also be helpful
for the instructor to do some pre-collecting in order to ensure adequate representation of orders
Part IV. Insects – overview of common orders
D. Life cycle – metamorphosis
E. Overview of some common orders – in phylogenetic order, from most primitive to most advanced:
Hemimetabolous
Odonata
Orthoptera
Blattodea
Mantodea
Phasmatodea
Hemiptera
Holometabolous
Neuroptera
Coleoptera
Diptera
Lepidoptera
Hymenoptera
For each order, give the following:
1. metamorphosis – hemi (“incomplete”) or holo (“complete”)
2. meaning of name (ex: Coleoptera = “sheath wing”), common names, examples
3. mouthparts & feeding habits
4. habitats
5. identifying characteristics
Part V. Identifying & grouping insects that have been collected
A. Have students work in groups of 2-3 to sort insects according to order. Focus should be on visual
identification and on getting orders – not on getting things to family, species, etc. It’s okay to make a
category for “unknowns.” Instructor can circulate and check accuracy and answer questions.
B. When small groups have finished, combine groups to get a “class collection,” labeling the orders and
putting “like species” together.
C. Class collection can be compared with the Ecolodge’s teaching collection. This should be saved until the
end of the activity – idea is for students to rely on their own classifications first, then compare later.
Insect-O-Rama – Page 2
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Part I. Insects – overview of ecology and morphology
A. Biodiversity in Costa Rica
Costa Rica comprises only 0.03% of land area in the world, and yet is one of the 20 countries with the greatest
biodiversity. There are 500,000 species identified in Costa Rica – this is 4% of the known species in the world!
Of these 500,000, over 300,000 are insects (60% of total identified species)! (InBio)
Important to study insects because they are the dominant group of animals on earth. They’ve been around for
350 million years vs 2 million years for humans.
Number of species known/named/identified is only a VERY small part of the actual number of species out there
– many remain unknown to science. Some estimates go as high as 30 million species!
B. Ecological roles of insects: What do insects do? What are they good for?
You might be most familiar with the insects you see around your home… mosquitoes, ants, bees,
grasshoppers, etc.
- Insects can be pests in the home (ants, moths, termites, cockroaches)
- Insects can be major agricultural pests (aphids, weevils, locusts)
- Insects harm humans (stings, bits, odors, agents in transmitting diseases)
But insects also play important ecological roles:
- Insects are the sole or major food item for many birds, fish, bats, etc.
- Important pollinators of flowering plants. 80% of pollination is by animals (most of that insects), the rest
is either wind or self-pollinating. Pollinate important crops like fruits, vegetables, and coffee.
- Herbivory–effects in nature and also damage to crops
And… insects are important for other reasons, as well:
- Insects provide important commercial products (honey, wax, silk, food coloring, etc.)
o Many cultures eat insects as a(n ecologically and economically) cheap source of protein
o Source for medical treatments: ex) Asthma beetle, maggots
- Important in scientific research (genetics, heredity, evolution, sociology)
- Important decomposers
- Can be used to solve crimes (progression of insects on decomposing bodies)
- Can tell us a lot about ecosystems (ex: aquatic insects tell us about water quality in streams)
- Can be used to control harmful/unwanted insects or weeds in agriculture (integrated pest
management/biocontrol)
- Inspire industry
o Architecture (termites), computer science (ants), design (biomimicry)
C. What is an insect?
What do we mean when we call something an insect? All forms of life are classified by taxonomists
according to the following scheme of classification. Each category is called a “taxon.” Here is an example of
how insects would be classified:
Domain: Eukaryota
Kingdom: Animalia (animals)
Phylum: Arthropoda (arthropods)
Class: Insecta (insects) (sometimes also called Hexapoda)
Order: we will be covering some of the more common orders today
Family
Genus
Species
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Basic characteristics of Arthropods.
-Arthro (meaning joint) and poda (meaning leg), “Jointed Leg”
-Segmented/jointed legs
-Exoskeleton made of chitin, similar to keratin in hair and nails of humans
-Bilateral symmetry
-Includes: Spiders, mites, scorpions, lobsters, crab, shrimp, and...Insects!
Basic characteristics of Insects. All insects have the following during at least some life stage:
- head (brain), thorax (wings & legs), and abdomen (digestive & reproductive parts)
- 3 pairs of legs (well, with the exception of Nymphalid butterflies, female Stresiptera, etc.)
- 2 pairs of wings (with the exception of some basal orders [firebrats, bristletails], and earwigs, etc.)
- 2 antennae
D. Morphological Identification.
● Mouthparts
-Mandibular (Chewing): Predators or Herbivores, Mantis or Caterpillar
-Beak (Piercing/Sucking): Food source could be plant or other insect, Some Bugs and Flies
-Sponging: House/Fruit Flies use to feed on liquids, secret enzymes to liquify food
-Proboscis (Siphoning): long tube used to draw nectar from flowers, Butterflies
● Eyes
-Most insects have compound eyes which consist of tiny lenses/facets to create a mosaic picture
-Do the eyes face forward? To the side? How well does it fly? Is it a predator or herbivore?
-Herbivores typically see further with poor focus
-Predators typically see nearer with higher focus
-All have ocelli used to detect light intensity
-Ocelli are used to orient in flight against the horizon
● Legs
-Saltatorial (Jumping): Hind leg of grasshoppers
-Raptorial (Grasping): Forelegs of Mantids
-Cursorial (Running): Cockroach legs
-Fossorial (Digging): Forelegs of mole crickets, most with these live underground
● Wings
-Membranous: thin, transparent, supported by tubular veins-Dragonflies/Bees
-Halteres: small, knobbed, vibrating organs that help balance in flight-Rear Wings of Flies
-Scaly: wings covered in colorful/unicellular scales-Butterflies/Moths
-Tegmina: protective, leathery wings not used in flight-Forewings of Grasshoppers/Crickets
-Elytra: thick, hardened wing without venation, used as protection-Forewings of Beetles
-Hemielytra: top half leathery, bottom half membranous-True Bugs
● Abdomen
-Cerci: paired appendages on tip of abdomen, usually have sensory function, often are larger in
males and used in mating, some used for defense (earwigs)
-Ovipositor: egg laying device found only in females, can be sturdy and stout or long and blade-like
-Stinger: modified ovipositor, used to deliver venom from a gland inside of abdomen
-Dorsoventral: flat across body
● Miscellaneous
-Nerve cord runs along the bottom of the body
-A tracheal system (a system of holes in the exoskeleton and tubes within the body) is used for
respiration; the circulatory system is separate from this process
-Aquatic insects have external gill structures for respiration
-Blood transports nutrients, waste, and hormones
-Taste organs can be found on the feet (flies) and antennae (ants)
-Some insects have tymphanic organs that allows them to hear, can be located on various parts of
the body
-Some insects have hairs on their body to enhance their sensory abilities
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Part IV. Overview of common orders.
A. Life cycle – metamorphosis
Metamorphosis refers to a major change of form or structure during development.
Metamorphosis is one of the key reasons why insects are so successful. Many insects have immature stages with
completely different habitats from the adults. This means that insects can often exploit valuable food resources
while still being able to disperse into new habitats as winged adults. The potential for adaptation and evolution is
greatly enhanced by metamorphosis.
Within the class Insecta, there are 3 subclasses:
Ametabola – only 2 orders, won’t talk about today
Hemimetabola
Holometabola
For reference, Ametabola, is the most primitive in the insect world. Insects in this order do not go through
metamorphosis and exit the egg in the form that they will retain for most of their lives. They also lack wings.
The “older” or more primitive condition is hemimetabolous, or “incomplete metamorphosis.” Roughly 12% of
insects go through this type of change. Hemimetabolous insects do not have a pupal stage. The general
appearance of the immature stages is somewhat similar to that of adults, although there may be some dramatic
differences in lifestyle. For example, many immature phases may reside in aquatic habitats, while their adult forms
are terrestrial or aerial. Only adult insects are able to reproduce, and only adult insects have functional wings (in
those species that have wings). The immature stages of these insects are generally called nymphs (or naiads if
aquatic) rather than larvae. Mayflies also have what is known as a subimago stage which is an extra molt between
juvenile and adult stages.
Holometabolous, or “complete metamorphosis”: Roughly 88% of insects go through this type of change. Many of
the major insect orders have a typical life cycle which consists of an egg, which hatches into a larva which feeds,
molts and grows larger, pupates, then emerges as an adult insect that looks very different from the larva. These
insects are often called 'Holometabolous', meaning they undergo a complete (Holo = total) change (metabolous =
metamorphosis or change). Typically see more complexity and evolutionary change in subclass Holometabolous.
Typical life cycle of a holometabolous
Insect, such as an ant
(egg, larva, pupa, adult)
adult)
Typical life cycle of a hemimetabolous
insect such as a dragonfly
(egg, various instars/immature phases (NOT LARVA),
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Subclass Hemimetabola – all of the orders in this subclass have incomplete metamorphosis
Order Odonata
Metamorphosis
Incomplete
Meaning of name
From Greek “odonto” – meaning tooth
Common names
Two suborders:
Dragonflies (suborder Anisoptera)
Damselflies (suborder Zygoptera)
Mouthparts and feeding habits
Chewing; Both adults & immatures are voracious predators
Habitats
Immatures: aquatic (slow moving water or vegetation)
Adults: usually near ponds, lakes, or streams
Immatures:
Labial “mask” adapted for catching prey (think “Aliens”)
Identifying characteristics shared
by dragon & damselflies
Adults:
Antennae short and bristle-like
Compound eyes large, often covering most of head
Four membranous wings with many veins and cross veins
Immatures:
Dragonflies have a robust body
Damselflies have a long, slender body and 3 leaf-like gills at rear of
abdomen (looks like a tail)
How to tell dragonflies and
damselflies apart
Spanish name
Adults:
Dragonfly eyes are on top and touching, Damselfly eyes are to the
side and separate
At rest, dragonflies hold wings “out,” while damselflies are able to
fold them back
Libélula
Facts about Odonata:
-
Ancient insects that have been around since before the age of the dinosaurs. Some Odonate fossils from the
Carboniferous period had wingspans of over a meter!
The compound eyes of some dragonflies may have up to 28,000 facets.
Immatures can live in tree holes or bromeliads. Some immatures can shoot out their labium and catch prey in only 25
milliseconds. They feed on other aquatic insects, and even small fish and tadpoles!
Many adult male dragonflies establish and defend territories along the perimeter of a lake or stream. Females will mate
only with males that hold a territory. Male damselflies (and perhaps some dragonflies) have a special flagellum
associated with the copulatory organ that can reach into a female's body and remove sperm deposited by another male
in a previous mating. Females can also choose which sperm to use.
Example of dragonfly adult and immature
Example of damselfly adult and immature
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Order Orthoptera
Metamorphosis
Incomplete
Meaning of name
From Greek "ortho" = straight and "ptera" = wing
Common names
Grasshoppers, locusts, katydids, crickets
Mouthparts and feeding habits
Chewing mouthparts, most herbivorous (cone-headed katydid
carnivorous)
Habitats
Terrestrial, vegetation
Identifying characteristics:
Hind legs large and modified for jumping
Many species have the ability to make and detect sounds
Antennae:
Grasshoppers: short (shorter than body)
Katydids and crickets: long (longer than body)
How to tell who’s who
Tympanic organs (“ears”):
Grasshoppers: located on midline of abdomen
Katydids and crickets: located on forelegs
Tarsi (lower leg parts):
Katydids have 4 tarsi
Crickets have 3 tarsi
Spanish names
Grasshopper: chapulin
Katydid: esperanza
Cricket: grillo
Facts about Orthoptera:
- Orthoptera probably arose during the middle of the Carboniferous period
- One of the largest and most important groups of plant-feeding insects
- In many species of Orthoptera, the males use sound signals (chirping or whirring) in order to attract a mate.
The sound is produced by stridulation -- rubbing the upper surface of one wing against the lower surface of
another wing, or the inner surface of the hind leg against the outer surface of the front wing.
- Each stridulating species produces a unique mating call. In fact, some species may be so similar to each
other that they can only be distinguished by their mating calls.
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Order Blattodea
Metamorphosis
Incomplete
Meaning of name
Derived from "blatta", the Greek word for cockroach
Common names
Roaches, Termites (recently added)
Mouthparts and feeding habits
Chewing; Scavengers or omnivores
Habitats
Terrestrial; various habitats
Most abundant in tropics & subtropics
Identifying characteristics
Antennae slender, filiform
Pronotum oval, shield-like, covering much of head and thorax
Legs adapted for running; tarsi 5-segmented
Front wings thickened; hind wings membranous, pleated
Cerci short, multi-segmented
Spanish name
Cucaracha
Facts about Blattodea:
- Some species are commonly found in close association with human dwellings and are considered pests.
- Cockroaches have an oval, somewhat flattened body that is well-adapted for running and squeezing into
narrow openings. Rather than flying to escape danger, roaches usually scurry into cracks or crevices.
- Much of the head and thorax is covered and protected dorsally by a large plate of exoskeleton (the
pronotum).
- When cockroaches lay eggs, the female's reproductive system secretes a special capsule around her eggs.
This structure, known as an öotheca, may be dropped on the ground, glued to a substrate, or retained
within the female's body. Production of an öotheca is a special adaptation found only in cockroaches and
praying mantids. This similarity suggests a close phylogenetic relationship between these groups and
explains why some taxonomists prefer to lump them into a single order (Dictyoptera).
- The American cockroach, Periplaneta americana, is an introduced species that probably originated in
Africa.
- Despite their bad reputation, only about a dozen species (out of 4,000 worldwide) are regarded as pests.
- Cockroaches are actually quite clean, they spend a lot of time cleaning themselves.
- Cockroaches have a waxy covering
- Important Decomposers, one Amazonian genus processes 5% of leaf litter
- Known for their ability to survive, their body contains Ethylene glycol, which keeps ice crystals from forming
and not damaging their organs, so they can come back to life from being frozen!
- Termites were recently grouped in this order because the same protozoa was found in their guts to process
dense foods (ie wood).
Example of adult and immature Blattodea
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Order Mantodea
Metamorphosis
Incomplete
Meaning of name
Derived from "mantis", the Greek word for these insects.
Common names
Mantids: Praying mantis
Mouthparts and feeding habits
Predators, usually of other insects; chewing mouthparts
Habitats
Terrestrial; usually cryptic to blend with environment
Identifying characteristics
Filiform antennae
Head triangular with well-developed compound eyes
Large, spiny front legs adapted for catching prey
Front wings thickened, more slender than hind wings
Spanish names
Mantis, Mantis religiosa
Facts about Mantodea:
- Mantids have elongate bodies that are specialized for a predatory lifestyle: long front legs with spines
for catching and holding prey, a head that can turn from side to side, and cryptic coloration for hiding in
foliage or flowers.
- Mantids are most abundant and most diverse in the tropics; there are only 5 species commonly
collected in the United States and 3 of these have been imported from abroad.
- A female mantid may eat her mate while he is still linked with her in copulo (presumably adaptive
because the probability of the male finding another mate is so low that he best secures his contribution
to the next generation in the form of a meal). However, this is atypical behavior observed mostly in a
laboratory setting, not in the wild.
- Although mantids usually feed on insect prey, they have been known to catch and eat small frogs,
lizards, and even birds.
- Like the cockroach, the females produce an ootheca around their eggs
- Only insect that can look behind them!
Example of Mantodea
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Order Phasmatodea
Metamorphosis
Incomplete
Meaning of name
Derived from the Greek "phasm" meaning phantom, refers to the
cryptic appearance and behavior of these insects.
Common names
Walking sticks, leaf insects, stick insects
Mouthparts and feeding habits
Mandibulate/chewing; all species are herbivores
Habitats
As the name "walkingstick" implies, most are slender, cylindrical,
and cryptically colored to resemble the twigs and branches on
which they live.
Identifying characteristics of
Phasmatodea
Antennae long, slender; body long and cylindrical
Wings often reduced or absent
Prothorax shorter than meso- or metathorax
Leg segments long and slender; tarsi 5-segmented
Spanish names
Insecto palo, Juan palo, Mula del diablo, Maria seca
Facts about Phasmatodea:
- The leaf and stick insects are closely related to Orthoptera and are sometimes grouped as a family or
suborder of Orthoptera.
- Most walking sticks are slow-moving, a behavior pattern consistent with their cryptic lifestyle.
- In a few tropical species, the adults have well-developed wings; most are wingless/have reduced wings.
- Stick insects are most abundant in the tropics – some species may be up to 30 cm in length. Sexually
dimorphic, females are larger than males.
- Some walking sticks are sold as pets. They are easy to rear if kept in a warm environment with fresh
foliage from their host plant. In Southern CA, escaped stick insects are becoming an invasive pest.
- Glands on the thorax of many species can produce a foul-smelling liquid that repels predators.
- When attacked by a predator, the legs of some phasmids may separate from the body. Some species can
even regenerate lost legs at the next molt. These are the only insects able to regenerate body parts.
- Some phasmids change color with changes in temperature, humidity, or light intensity.
- Some are parthenogenic, which means that they can reproduce without being near the opposite species.
This can be good if the environment is static because you don’t need to continue adapting. This can be
bad if the environment is constantly changing because the genetic diversity will deteriorate over time.
- Eggs look like seeds and leaf cutter ants will carry them to their colony and protect them.
- Myth in parts of Costa Rica that if you hold one, it will dry you out.
Example of a walking stick
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Order Hemiptera
Metamorphosis
Incomplete
Meaning of name
Hemiptera means "half wing" – part of the first pair of wings is
toughened and hard, while the rest of the first pair and the second
pair are membranous
Common names
Suborders Homoptera and Heteroptera
Heteroptera: “True bugs” (True Bugs can also refer to Hemiptera)
Homoptera: leaf hoppers, cicadas, aphids
Mouthparts and feeding habits
Piercing/sucking mouthparts
Heteroptera: diverse feeding habits
Homoptera: all are terrestrial herbivores, suck plant juices
Habitats
Heteroptera: extremely diverse – terrestrial, aquatic, etc.
- Terrestrial species often associated with plants, feed in vascular
tissues or on the nutrients stored within seeds. Can be
scavengers in the soil or underground in caves or nests. Some
are predators on a variety of small arthropods
- Bed bugs, and other members of the family Cimicidae, live
exclusively as ectoparasites on birds and mammals
- Aquatics can be found on the surface of both fresh and salt
water, near shorelines, or beneath the water surface in nearly all
freshwater habitats.
Homoptera: terrestrial herbivores
Identifying characteristics
Piercing mouthparts
X or triangle shape when looking at wings (Heteroptera only)
Facts about Hemiptera:
- Homoptera are among most abundant herbivores found in terrestrial habitats. Many species are pests of
cultivated plants. Aphids and leafhoppers are important carriers of plant diseases.
- Dactylopius coccus, the cochineal insect, is the source of a bright red dye formerly used in the textile
industry. It is a scale insect that lives on prickly pear cacti.
- Water striders in genus Halobates are only true marine insects –on surface of Pacific Ocean
- Peanut-headed bug, La machaca, has a false head and an associated myth that if you touch one you need
to have sex within 24 hours or you die.
- Membracidae: thorn mimics
- Grammar plays a big role in common names. A true bug has a space between. For example, a ladybug
(Coleoptera) vs a stinkbug (Hemiptera). The same is true for flies. For example, a dragonfly (Odonata) vs
a fruit fly (Diptera).
Examples of Heteroptera
Examples of Homoptera
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Suborder Holometabola – all of the orders in this subclass have complete metamorphosis
Order Neuroptera
Metamorphosis
Complete
Meaning of name
From the Greek word "neuron" meaning sinew and "ptera"
meaning wings. The modern English translation "nerve-wings" is
appropriate because of extensive branching in wing veins of most
Neuroptera.
Common names
Three suborders within Neuroptera:
Planipennia (ant lions, lacewings)
Megaloptera (dobsonflies and alderflies)**
Raphidoidea (snakeflies)***
** Megaloptera is sometimes grouped as a separate order
***So is Raphidoidea (Raphidioptera)
Mouthparts and feeding habits
Megaloptera: immatures predatory; adults rarely feed
Planipennia & Raphidoidea: most immatures & adults predatory
All: chewing mouthparts (male Megaloptera have exaggerated,
non-functional mouthparts [sexual selection])
Habitats
Adults: terrestrial
Immatures: Megaloptera immatures are aquatic; rest are terrestrial
Identifying characteristics
Antennae filiform, multisegmented
Front and hind wing membranous, similar in size
Extensive branching of venation in all wings
Facts about Neuroptera:
-
-
The taxonomy of this order and its suborders are very hotly debated.
Antlion larvae live in the soil and construct pitfall traps to snare prey. Think the Sarlacc from Star Wars.
The larvae of antlions and lacewings have specialized mouthparts with large, sickle-shaped mandibles and
maxillae that interlock to form pincers. Once impaled on these pincers, a prey's body contents are sucked
out through hollow food channels running between the adjacent surfaces of the mandibles and maxillae.
As adults, all neuropterans have two pairs of membranous wings with an extensive pattern of veins and
cross veins. At rest, the wings are folded flat over the abdomen or held tent-like over the body. Most
species are rather weak fliers.
Examples of Neuroptera
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Order Coleoptera
Metamorphosis
Complete
Meaning of name
From the Greek words "koleos" meaning sheath and "ptera"
meaning wings, refers to the modified front wings which serve as
protective covers for the membranous hind wings
Common names
Beetles and weevils
Mouthparts and feeding habits
Strong mandibulate/chewing mouthparts; diets varied
Habitats
Varied – terrestrial, aquatic, burrowing, etc.
Identifying characteristics
Elytra!! – hardened forewings – defining characteristic
Front wings (elytra) are hard and serve as covers for the hind
wings; meet in a line down the middle of the back
Hind wings large, membranous, folded beneath the elytra
Chewing mouthparts (sometimes at tip of beak or snout)
Tarsi 2- to 5-segmented
Spanish name
Abejón (beetle), Escarabajo (Scarab), Mariquita (Ladybug)
Facts about Coleoptera:
- Coleoptera is the largest and most diverse order in the class Insecta. Coleoptera is also the largest order in
the animal kingdom. It includes 40% of all insects and nearly 30% of all animal species.
- Many beetles are regarded as major pests of agricultural plants and stored products. “La broca” is a coffee
farm pest and can be devastating.
- Scavengers and wood boring beetles are useful as decomposers and recyclers of organic nutrients.
- Predatory species, such as ladybugs, are important biological control agents of aphids and scale insects.
- Two families of Coleoptera are bioluminescent (produce light). Fireflies (family Lampyridae) and glowworms
(family Phengodidae) have light-producing organs in the abdomen. The 1st layer of cells have a reaction
and the 2nd layer of cells reflect light.
- Because the elytra are fairly hard structures, beetles have a better fossil record than many other insect
groups do; the oldest fossil beetles are Permian.
- In Costa Rica, about 3,000 species have been identified so far of an estimated 35,000. Worldwide 400,000
species have been identified. USA Junebugs=CR Maybugs
- Aquatic beetles swim w/ an air bubble.
- Curculionidae: Weevil family, largest; 50 families produce sounds
Example of a beetle
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Order Diptera
Metamorphosis
Complete
Meaning of name
From the Greek words "di" meaning two and "ptera" meaning
wings – true flies have only a single pair of wings.
Common names
True flies – include house flies, mosquitoes, black flies, crane flies,
horseflies, midges, fruit flies, blow flies, etc.
Mouthparts and feeding habits
Sucking mouthparts – scavenger (dead organic matter), predators,
or parasites. A few are herbivores (ex: fruit flies)
Immatures: Aquatic, semi-aquatic, or moist terrestrial. Found in
soil, plant/animal tissue, carrion/dung.
Habitats
Adults: wide range of habitats, enormous variation in appearance
and lifestyle.
Identifying characteristics
All flies have one pair of wings (front); hind wings reduced
(halteres). Only the membranous front wings are used for flying –
the halteres vibrate during flight & help maintain balance.
Spanish name
mosca (fly); mosquito or zancudo (mosquito);
tábano (horse fly); tórsalo (bot fly);
Facts about Diptera:
- The Diptera are divided into 2 sub-orders: Nematocera and Brachycera. Nematocera are the most primitive
flies, with long, skinny antennae (such as mosquitoes.) Brachycera: more advanced flies, such as horse
flies (family Tabanidae). Within Brachycera, there is a sub-group called Cyclorrapha – these are the most
complex flies, such as house flies.
- The Diptera probably have a greater economic impact on humans than any other group of insects. Some
flies are pests of agricultural plants, others transmit diseases to humans and domestic animals
- But – many are beneficial as well: pollinate flowering plants, assist in the decomposition of organic matter,
or serve as biocontrol agents of insect pests.
- Hover flies are probably the most precise fliers among all insects.
Examples of Diptera adults and larvae
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Order Lepidoptera
Metamorphosis
Complete
Meaning of name
From Greek "lepido" for scale and "ptera" for wings, refers to
flattened hairs (scales) that cover body & wings of adults.
Common names
Butterflies, moths, skippers
Mouthparts and feeding habits
Tubular proboscis for sipping nectar, rotting fruit, poop, etc.
Habitats
Immatures: vegetation, roots, stems, leaf miners
Adults: aerial, vegetation
Identifying characteristics
Immatures: Caterpillar-like; chewing mouthparts; prolegs
Adults: Body & wings covered with small overlapping scales
3 groups within Lepidoptera: butterflies, moths, skippers
Butterflies: Antennae knobbed at tip; diurnal; brightly colored
(usually)
How to tell who’s who
Moths: Antennae thread-like, spindle-like, or comb-like; antennae
have “hairs” or appear fuzzy; usually nocturnal and with drab
coloration (usually)
Skippers: Antennae hooked at end; body & wings stocky and
square; usually bright yellow/orange (usually)
Can always tell by looking at pupa (cacoon vs. chrysalis)
Spanish name
Mariposa (butterfly); mariposa nocturna/pollila (moth)
Facts about Lepidoptera:
- Lepidoptera is the second largest order in the class Insecta (Coleoptera is the largest).
- Nearly all lepidopteran larvae are called caterpillars and nearly all are herbivores. Some species eat
foliage, some burrow into stems or roots, and some are leaf-miners.
- Adult butterflies are distinctive for their large wings (relative to body size) which are covered with minute
overlapping scales. Scales often produce distinctive color patterns that play an important role in courtship
and intraspecific recognition.
- Folks in San Luis have a superstition that if the patterns on moths’ wings look like numbers, then those are
the numbers you should play the Lottery for a winning ticket!
- About 80% of order are moths
- Dangerous to remove a caterpillar from a plant because that is likely its preferred food
Insect-O-Rama – Page 15
Updated 27Oct2013
Order Hymenoptera
Metamorphosis
Complete
Meaning of name
From Greek "hymen" meaning membrane and "ptera" meaning
wings. Is also a reference to Hymeno, the Greek god of marriage.
The name is appropriate not only for the membranous nature of the
wings, but also for the manner in which they are "joined together as
one" by the hamuli.
Common names
Ants, bees, wasps
Mouthparts and feeding habits
Unspecialized chewing, except nectar-feeding bees
Habitats
Terrestrial; various
Identifying characteristics
- Compound eyes well developed
- Tarsi usually 5-segmented
- Hind wings smaller than front wings, linked together by small
hooks (hamuli).
- Narrow junction (“pedicel”) between thorax and abdomen
- 2 pairs of wings, except worker ants (wingless) and “velvet ants”,
which are wasps that are also wingless
Spanish name
Avispa (wasp); abeja (bee); hormiga (ant)
Leaf cutter ants are called zompopas, Army ants ronchadoras
Facts about Hymenoptera
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The Hymenoptera is the only order besides the Blattodea (termites) to have evolved complex social systems with
division of labor known as eusociality. Depending on your definition, other animals can also fit under this label. BUT –
not all Hymenoptera are social; many live a solitary life, coming together only for mating.
Honeybees and true ants have developed regimented social systems in which members are divided into worker, drone
(“drone” usually used just for bees), & queen castes. Such social hymenoptera may live in nests or hives of many
thousands (can be millions for some ants) of individuals, all descended from a single queen (usually).
Important pollinators of flowering plants. Flowers pollinated by bees are typically yellow or blue and often have patterns
visible only under ultraviolet light, which bees can see. Other plants may be pollinated by ants, or may rely on ants
living within them to keep predators away. Many of these plants produce large quantities of nectar or other fluids for the
ants.
Most Hymenoptera are extremely beneficial, either as natural enemies of insect pests (parasitic wasps) or as
pollinators of flowering plants (bees and wasps).
o Exceptions include red imported fire ants (common in southeaster US), argentine ants (in the southeast
and on the west coast), raspberry crazy ants, little fire ant (wasmania aeropunctata), japanese needle ant,
etc.
In the Hymenoptera, females develop from fertilized eggs (lol usually), males from unfertilized eggs.
Aculeate Hymenoptera (certain wasps, bees, and ants) are the only insects that can sting. Not all ants can sting.
Orchid poachers greatly affect orchid bees (Euglossine). Orchid bees use scents provided by the orchid to generate
perfume to attract males.
Use pheromones for communication (“Bee Dance”)
Ichneumonidae are a type of wasp known for its very narrow junction.
Ants are only 1% of insect species but 80% of the biomass, which is equal or greater than the biomass of humans and
possibly even all mammals.
Examples of Hymenoptera
Insect-O-Rama – Page 16
Updated 27Oct2013
Appendix
List of all insect orders with common names, in phylogenetic order from most primitive (oldest)
to most advanced (most recently evolved)
Ametabola
Order Archeognatha (Bristletails)
Order Thysanura (Silverfish, Firebrats)
Hemimetabola
Order Ephemeroptera (Mayflies)
Order Odonata (Dragonflies, Damselflies)
Order Plecoptera (Stoneflies)
Order Embioptera (Webspinners)
Order Orthoptera (Grasshoppers, Crickets)
Order Grylloblattodea (Rockcrawlers)
Order Mantophasmatodea (Gladiators)
Order Dermaptera (Earwigs)
Order Blattodea (Cockroaches and Termites)
Order Mantodea (Praying Mantids)
Order Phasmatodea (Walkingsticks)
Order Zoraptera
Order Hemiptera
Suborder Heteroptera (True Bugs)
Suborder Homoptera (Aphids, Cicadas, Leafhoppers, et al.)
Order Thysanoptera (Thrips)
Order Psocoptera (Booklice, Barklice)
Order Phthiraptera (Lice)
Holometabola
Order Neuroptera (Lacewings, ant lions)
Order Megaloptera (Dobsonflies)
Order Coleoptera (Beetles)
Order Strepsiptera (Twisted-wing Parasites)
Order Hymenoptera (Ants, Wasps, Bees)
Order Mecoptera (Scorpionflies)
Order Trichoptera (Caddisflies)
Order Lepidoptera (Moths, Butterflies)
Order Diptera (True Flies)
Order Siphonaptera (Fleas)
Insect-O-Rama – Page 17
Updated 27Oct2013