The Insect Factor inUrban Plant Protection

Bob Gara

Every where you look

There are fungiall around us, some 100,000 species in fact.

Bob will soon tell you that there are a lot of fungi in the world.

Ther

e ar

e a

Ther

e ar

e a

MIL

LIO

N

MIL

LIO

Nsp

ecie

s of

inse

cts!

spec

ies

of in

sect

s!

Yea, and 500,000 ofthose species arebeetles.

But

Several times I’ve visited southern Chile, and collected insects:

• find undescribed species• new genus• even new families

There may be well over 5 - 10 million insect species

By sheer numbers alone, insectsbecome important to us: especiallyin urban horticulture

1. Destroy seeds beforethey are collected

2. Destroy seeds when stored &when planted in nurseries

3. Urban plants are defoliated and become ugly

4. Mature trees and plants arekilled by barkbeetles, aphids etc.

5. Wooden products are destroyedby termites, carpenter ants andpowderpost beetles

BOB GARA

Speakingof levers

Give me a lever longenough and I can liftthe world.

1. Jointed appendages, 2. 1. Jointed appendages, 2. Bilateral-symmetry, 3. Body Bilateral-symmetry, 3. Body composed of rings, composed of rings, 4. Exoskeleton, & 5. Dorsal 4. Exoskeleton, & 5. Dorsal heart and ventral nervous heart and ventral nervous systemsystem

Don’t forget:

There are about 20 classes of arthropods & the best way to getan overview is to look at theirevolutionary history (phylogeny).

R.E. Snodgrass

R.E. Snodgrass

Snodgrass developed a theory onthe evolution of the arthropods bystudying the movement of ancestralappendages in embryos of theArthropoda

Annelid

Onychophora

Trilobite

Chilopod

Insecta

This is what Snodgrass suggested

If this sequential development ofappendages is correct (as seen inthe embryos), are there really membersof these stages? Is all this real?

Are there onychopherans?

Even fossils

Are there trilobites?

In any case, position of the mouthpartsvis-à-vis the various arthropods has created this divide: Chelicerata & Mandibulata

No antennae

Let’s look at some Chelicerata

Chelicera

Pedipalp

1. Horseshoecrab

2. Scorpion

Chelicerae

Pedipalps

The Economically ImportantChilicerates -- ARACHNIDA

SpidersMitesTicks

Chelicera

Pedipalp

Fang

3. Spider (Class Arachnida)

Larval Nymphal Adult

4. Ticks (Class Arachnida)

The hard ticks: ixodidae

Lyme diseasebacteria

Fused Chelicerae

Pedipalp

Chelicerae and pedipalpsof a hard tick (Ixodidae)

Chelicerae

Pedipalp

Gall mite

Spider mite

5. Couple of mites (Class Arachnida)

Blister mite

Spider mites

Chelicerae

Chelicerae

Ch

elic

era

e

Pedipalp

More ticks & mites: Arachnida

Let’s Talk About the Subphylum:Mandibulata

Let’s go back some 400 millionyears ago: Silurian Period

Era Millions yrs ago Periods Life forms

Paleozoic 440

SilurianSilurian Scorpions, millipedes,

rise of fish

500 Ordovician 1st vertebrates

600 Cambrian 1st arthropods trilobites and some others

Precambrian Primitive invertebrates floating around

1st land animals!

A big breakthrough during Siluriantimes was that appendages of thearthropod began to be closely associated with the mouth -- eveninside the mouth as in MANDIBULATA

Embryo-genesis ofan insect: segmentsI-4 will go around thehead and into the mouth: hence,MANDIBULATA.

Old Snodgrasswas right on.

Insecta

Crustacea

Centipedes Millipedes

Mandibulata

Protoarthropod

So, during the Silurian the newland animals quickly diversifiedand evolved

Let’s mention the• Crustaceans• Centipedes• Millipedes

Centipede

Millipede

Poison claw

Classes: Chilopoda & Diplopoda

Crustacea

Hi!

• Have 2-antennae• Complex mouthparts inside the mouth• Cephalothorax

The Class: InsectaInsecta• 3-body regions• 1-pair of antennae• 3-pairs of legs• Adults are winged

Of course, insects are arthropods: have exoskeletons. What are some advantages of having the skeletonon the outside?

• Physical protection

• Great mechanical advantage

• Prevents desiccation

• Led to the fact insects havecomplete metamorphosis!

Arachnida

Spiders Mites Ticks

Chelicerata Mandibulata

The Chelicerata have theirmouthparts outside the mouth

Review

The Economically ImportantChelicerata – Class, Arachnida

A rhododendron mite

Che

licer

ae

Identify the chelicerae

1. The phylum Arthropoda is divided into the subphyla Chelicerata and Mandibulata. Name two organisms from each group: ________________ and __________________________. Label the mouthparts of this typical mite.

Since all arthropods, including the insects, have a hardexoskeleton they have to changeit in order to grow. This processis called MOLTING.

Cicadamolting

The fact that insects molt has ledthem to conquer just about everyniche on earth. Because:

when insects molt, they undergoa change in form.

Hmmmm, the word for “change-in-form” is METAMORPHOSIS.

No Metamorphosis

Incomplete Metamorphosis

This is a silver fish

This is a silverfish

Gradual Metamorphosis

Now for the greatest inventionin the world !!

Complete Metamorphosis

Complete Metamorphosis

Eggs

Lava (maggot)

Adult

The Pupa !

Complete Metamorphosis

Antenna

Compound eye

Ocellus

Mouth (mandible)

The Head

Hi, I’m Walt

Labium

Labial palp

Maxillary palp

Labrum

The Mouthparts

Labium

Can’t see themandibles

Labrum

Mandibles

Mx &Mx palps

Labium & Lb palps

I really want you to seehow the mouthparts fit

Again, the mouthparts

The Hemiptera: includes the bugs

Hemipteraincludes theaphids, scales,cicadas etc.

Aphids: Aphididae

Have piercing-sucking mouth parts

The Hemiptera havePiercing-sucking mouthparts

Piercing-sucking mouth parts

Mx

MxMnd

Cross section

The stylets (piercing-sucking)mouthparts of Hemiptera

More on aphids

MidgutForegut Hindgut

Digestive system of an insect

Filter chamberof aphids & otherhomopterans