World of InsectsWorld of InsectsCharacteristics, Orders, Characteristics, Orders,

and Collectingand Collecting

What You Should Know What You Should Know About Insects …About Insects …

Taxonomy•Kingdom – Animalia•Phylum – Arthropoda

•Class - Insecta

Insects Are Insects Are ArthropodsArthropods

• Insects are the largest group of Arthropods

• Jointed appendages (bendable)• Segmented bodies• Exoskeleton of Chitin that

must be molted to grow• Related to spiders, ticks,

scorpions, millipedes, crustaceans

MAIN CHARACTERISTICSMAIN CHARACTERISTICS

•Three body regions – head, thorax, and abdomen

•One pair antenna (head)•Six legs or 3 pairs (thorax)•One-two pairs of wings

(thorax)

Count the Legs!Count the Legs!

There are ALWAYS SIXSIX legs, and they are attached to the THORAXTHORAX

AntennaAntenna• One Pair on head• Jointed• Sensory (smell)• Called “feelers”• Filiform most

common shape (segments = size)

• May be modified

FILIFORM

Antenna Modifications

Wings or No WingsWings or No Wings•Most adults have

2 pairs•Called forewings

and hindwings•Some insects are

wingless (silverfish, fleas, some termites and ants)

More on WingsMore on WingsA network of Veins strengthens

wings

MEMBRANEOUS (clear) MEMBRANEOUS (clear) WINGSWINGS

Some Wings Are Covered With Powdery Scales

BUTTERFLIES & MOTHSBUTTERFLIES & MOTHS

Wings May Be ModifiedWings May Be Modified• Order Diptera

(flies)• 2nd pair of

wings modified into HALTERES

• Used for balance

• Makes flies hard to catch!

Beetle WingsBeetle Wings

• Hard Forewing called Elytra• Meet in straight line down the abdomen• Membranous hindwings folded underneath (flight)

ELYTRA

CIRCLECIRCLE THE INSECTSTHE INSECTS

INSECT ORDERSINSECT ORDERS

INSECTS WITH WINGSINSECTS WITH WINGS

Why Can’t I Call All of Why Can’t I Call All of Them Bugs?Them Bugs?

• EVERY BUG EVERY BUG is an insect, but NOT ALL NOT ALL INSECTSINSECTS are bugs!

• True BUGS are in the Order HEMIPTERAHEMIPTERA

• Posterior thorax is Posterior thorax is triangulartriangular; called ; called SCUTELLUMSCUTELLUM

• Last 3Last 3rdrd of wing CLEAR of wing CLEAR• All have piercing All have piercing

/sucking mouthparts/sucking mouthparts

Which of these are Which of these are BUGS?BUGS?

ALLALL

More Hemipterans

Assassin Assassin BugBug

Giant Giant Water BugWater Bug Leaf HopperLeaf Hopper

Water BoatmanWater Boatman

ColeopteraColeoptera• Called beetlesbeetles• Tough exoskeletonexoskeleton• Forewings called ElytraElytra•Fly with membranous hindwings•Larva called grubs Rhinoceros Rhinoceros

beetlebeetle

Cucumber Cucumber beetlebeetle

Ladybird beetleLadybird beetle

Diptera

• Contains mosquitoesmosquitoes & fliesflies

• One pair One pair functional wings

• Club-shaped haltereshalteres for balance

• Bodies often hairyhairy

Green Bottle Green Bottle flyfly

Hover FlyHover Fly

Fruit Fly

Aedes MosquitoAedes Mosquito

Dermaptera• Called earwigsearwigs• Long, flatflat bodies• ForcepsForceps (pincers)

on end of abdomen

• Short, hard Short, hard forewings forewings (membranous wings folded underneath

• Large jaws (mandiblesmandibles) on head

EARWIG EATING EARWIG EATING CATERPILLARCATERPILLAR

PINCERS

Orthoptera• Grasshoppers, Grasshoppers,

locusts, crickets, locusts, crickets, katydidskatydids

• Very longlong bodies• Rear legs modified

for jumpingjumping• Females with egg

laying tube (ovipositor on end of abdomen)

• Often communicate with chirping sounds

Lepidoptera• Moths, butterflies, & Moths, butterflies, &

skippersskippers• SiphoningSiphoning mouthparts

coiled under head• Powdery scales Powdery scales on

wings• Butterflies fold wings

flatflat above body at rest

• MothsMoths are night activenight active• Important plant

pollinators

Neuroptera• LacewingsLacewings• Net veined Net veined

wings• Small, delicate

insects• Long antennaLong antenna• Predators on

other insects• May feed on

nectar

Isoptera• TermitesTermites• Live in coloniescolonies• Feed on woodwood• Soft bodies Soft bodies &

short antenna• CastesCastes –

workers, soldiers, kings, and queen

Homoptera

• Cicadas, leaf Cicadas, leaf hoppers, hoppers, wingless aphidswingless aphids

• If wings present, held roof like roof like over body & membranousmembranous

• Piercing-suckingPiercing-sucking mouthparts

Aphids

Cicada

Leafhopper

Odonata• Dragonflies & Dragonflies &

damselfliesdamselflies• DragonfliesDragonflies hold

clear wings spread perpendicularperpendicular to body at rest

• DamselfliesDamselflies hold clear wings together over together over abdomenabdomen

Hymenoptera

• Bees, ants, Bees, ants, waspswasps

• Narrow waiNarrow waist connects thorax & abdomen

• Abdomen Abdomen curved curved downward

• May have stingerstinger on end of abdomen

Carpenter bee

Red ant

Yellow jacket

INSECT ORDERSINSECT ORDERS

WINGLESS INSECTSWINGLESS INSECTS

ThysanuraThysanura• Called Silverfish• Found around

houses or outside under stones or wood

• Fast runners• Damage books• Secretive and

active at night. • Flat, long bodies• Long antennae• Three, long, tail like

appendages

SiphonapteraSiphonaptera

• FleasFleas• EctoparasitesEctoparasites• Bodies

laterally compressed

• Enlarged hind hind jumping legsjumping legs

• Very short antenna

Anoplura• Sucking liceSucking lice• ParasitesParasites of

mammals• Very smallsmall• HeadHead and body body

licelice are examples

• Attracted to children’s fine hair

• Carry disease

Mallophaga• Biting liceBiting lice• External

parasites on birds & birds & mammalsmammals

• Broad head Broad head & flattened body

• Feed on dead skin, feathers, and fur

MetamorphosisMetamorphosis

CHANGE IN FORM FROM EGG TO ADULTCHANGE IN FORM FROM EGG TO ADULT

IncompleteINCOMPLETEINCOMPLETE

METAMORPHOUMETAMORPHOUSS

Insects change shape gradually!

CompleteCompleteMetamorphosisMetamorphosis

Four stages that all look

different

Amorphic InsectsAmorphic Insects

SpringtailsSpringtailsSilverfishSilverfish

Insects with Insects with CompleteComplete MetamorphosisMetamorphosis

• ColeopteraColeoptera (beetles)• HymenopteraHymenoptera (bees,

ants, wasps)• DipteraDiptera (flies)

LepidopteraLepidoptera (butterflies)

EGG EGG LARVA LARVA PUPA PUPA ADULT ADULT

Insects with Insects with IncompleteIncomplete MetamorphosisMetamorphosis

• SiphonapteraSiphonaptera (fleas)• IsopteraIsoptera (termites)• OrthopteraOrthoptera

(grasshoppers & crickets)

• HemipteraHemiptera (true bugs)• HomopteraHomoptera (cicadas &

hoppers)

EGG EGG NYMPH NYMPH ADULT ADULT

Wings NOT fully

developed