Entomology Review or

What’s that Bug?

Lady

Beetle

larvae

spiders, ticks, and

centipedes (chilopods)

millipedes (diplopods)

snails (molluscs)

mites (arachnids)

spiders (arachnids)

pillbugs (crustaceans)

Not all “bugs” are

insects.

Phylum: Arthropoda Arthropoda

Class: Insecta Arachnida

Order: Diptera Araneae

Family: Muscidae Theridiidae

Genus: Musca Latrodectus

Species: domestica hesperus

Common name: house fly black widow

Remember this?

two main body regions - cephalothorax

(head and thorax fused together)

abdomen

Arachnids: spiders, ticks, scorpions, mites

no antennae

simple eyes

four pairs of jointed legs

no wings

Arachnids

• Spiders and their Kin

Spiders

Ticks

Scorpions

Mites

• Spiders are mostly beneficial

Wings - None, One or Two Pairs

Three Distinct Body Regions: Head, Thorax, Abdomen

Jointed Legs - Three Pairs Antennae - One Pair

Undergoes Metamorphosis

Insect Characteristics

chewing mouthparts

piercing-sucking mouthparts

siphoning

Orthoptera - crickets, grasshoppers

Hemiptera - true bugs

Homoptera - aphids, scale, hoppers

Lepidoptera - butterflies, moths

Coleoptera - beetles, weevils

Diptera - flies, mosquitoes

Hymenoptera - bees, ants

Common Insect Orders

Characterized by:

Mouthparts

Type of legs, wings, antenna

Metamorphosis

Nymphs resemble adults, except for

being wingless. Both adults &

nymphs cause damage.

Moderate to large, hard-bodied

adults with two pairs of wings.

Front wings are hard, leathery

ORTHOPTERA - grasshoppers, locusts, crickets, mantids, cockroaches

Gradual metamorphosis, chewing mouth

parts

HEMIPTERA - true bugs

Gradual metamorphosis, Piercing-sucking

mouthparts in nymphs (immatures) and

adults

Recognized by

triangle on back

Harlequin Bug

HOMOPTERA -aphids, scales, leafhoppers, cicadas, whiteflies, mealybugs

Gradual metamorphosis, piercing-

sucking mouthparts in nymphs

(immatures) and adults

Small, soft-bodied insects,

except for cicadas

Aphids

Mealybugs are considered a type

of scale. They are oval,

segmented, and covered with wax.

Scales may be small, round or football-

shaped, and armored (California red scale)

or soft-bodied (cottony cushion scale).

HOMOPTERA

Whitefles are tiny sap-suckers found in

vegetables, ornamentals, and citrus trees.

HOMOPTERA -aphids, scales, leafhoppers,

cicadas, whiteflies, mealybugs

Leafhoppers feed on undersides of

leaves, transmit virus diseases. Hosts

are: beans, cucurbits, potatoes,

eggplants, grapes, and apples

Butterflies & Moths: Lepidoptera

• Complete metamorphosis

• Larva are caterpillars

• 4 wings, often showy

• Adults are nectar feeders

Moth vs. Butterfly

Moth

• Antennae are feathery or wiry

• Wings at rest – out-stretched, folded or angled

• Day & night

Butterfly

• Antennae end in a club

• Wings at rest out-stretched or held vertically

• Day-time only

LEPIDOPTERA - butterflies, moths

Larvae - chewing

Adults - siphoning

Complete metamorphosis

Mouthparts

Larvae are worm-like,

voracious feeders with prolegs

on abdomen and thorax. Adults are soft-bodied with two

pairs of membranous wings

covered with small scales.

Leaf-eating caterpillars (tomato hornworm, armyworms,

loopers) chew irregular holes. Many small caterpillars

roll leaves to form shelters.

LEPIDOPTERA - butterflies, moths

Beetles = Coleoptera

• More Beetle species than all other animals

• Hard “shelled” forewing

• Vegetarians, predators, scavengers & parasites

COLEOPTERA - beetles, weevils

Complete metamorphosis

Chewing Mouthparts

(adults and larva)

Larvae (grubs, wireworms,

borers) have head capsule

COLEOPTERA - beetles, weevils

Adults have two pairs of wings.

Horny, leathery front wings (elytra)

cover membranous hind wings

underneath, used for flying.

COLEOPTERA - beetles, weevils

Flea beetles, wireworms (click beetle larvae), cucumber

beetles, vegetable weevils, and green fruit beetles are

common pests in California home vegetable gardens

Lady beetles (ladybugs) are beneficials

Flies & Mosquitoes - Diptera

Only 2 wings (1 pair)

Mouth parts adapted for sucking

or piercing & sucking

Complete metamorphsis

Important garden and agricultural pests include the

cabbage maggot, onion maggot, apple maggot, walnut

husk fly, fruit flies, and leafminers

DIPTERA - flies, mosquitoes, gnats, midges

cabbage maggot

onion maggot apple maggot

walnut husk fly

Hymenoptera: Ants, Wasps, Bees, Sawflies

• Narrow waists

• Chewing mouthparts

• Complete metamorphosis

• Can have up to 2 pairs of membranous wings

HYMENOPTERA - bees, wasps, ants, sawflies

Many species are beneficial,

are parasites, natural

enemies or biological control

agents of many pest insects

Raspberry horntail

Pear sawfly larvae Leafcutter wasp

Rose sawfly damage

HYMENOPTERA - bees, wasps, ants, sawflies

WHAT IF YOU DON’T SEE A BUG?

Symptoms or signs of insect attack: Chewed foliage or fruit

Grape leafhopper

Symptoms or signs of insect attack: bleached, stippled or mined leaves

Symptoms or signs of insect attack:

distortion (swelling, twisting, cupping) of

plant parts

Symptoms or signs of insect attack: Dieback of twigs, stems or plant

Peach tree borer

Symptoms or signs of insect attack: presence of insect-related debris

sooty mold

frass

So What’s that Bug?

Red-humped caterpillar

Bark Beetle

Spider mites – not visible to

the naked eye, look for

webbing, suck juices from

plants

Stink bugs attack stone fruits, broccoli,

cabbage, tomatoes. They give off an

offensive odor when disturbed.

Centipede: not an insect,

but a general predator of

insects

Curled, distorted leaves

and sticky honeydew

exudates on leaves are

strong signs of aphid

infestation.

Tomato Hornworm: voracious

muncher of leaves

Lygus bugs

attack beans,

strawberries and

orchard crops.

Assassin Bug: eats beetles,

caterpillars, hornworms & other

insects

Syrphid fly larvae are important

predators of aphids & scales

Earwig, chews flowers & fruit,

can also be beneficial predator

by eating insects & larvae

Walnut Husk Fly: 2 wings,

compound eyes

Codling Moth: larvae are

“worm” in the center of

apples & pears, look for

stings, remove overwintering

pupae

Lacewing: good bug, preys on

aphids and whiteflies

Cucumber beetle: bad

bug, eats crops &

foliage

Scales: suck plant juices

under their covering