AQUATIC INSECTS

I. Phylum Arthropoda A. Major characteristics 1. Jointed appendages and…

2. An exoskeleton of chitin

3. Segmented body

II. Classes of Arthropods B. Class Diplopoda A. Class Arachnida C. Class Chilopoda D. Class Crustacea E. Class Insecta

III. Characteristics of class Insecta Only class with wings One pair of antenna abdomen thorax head

Kingdom Animalia Phylum Arthropoda Class Insecta Order Diptera IV. Classification (use the common mosquito as an example) Kingdom Animalia Phylum Arthropoda Class Insecta Order Diptera Family Culicidae Genus Culex Species pipiens Scientific name: Culex pipiens

V. Examples of AQUATIC INSECTS

A. The Seven Orders

1. Ephemeroptera

mayfly nymph (naiad)

2. Odonata

DAMSELFLY

3. Plecoptera

stonefly nymph

4. Hemiptera

water boatman

back swimmer

water strider

GIANT WATER BUG

WATER SCORPION

5. Coleoptera

Diving beetle larva

whirligig beetle

Water penny

6. Trichoptera

caddisfly larva

7. Diptera

mosquito

red-tailed maggot.

Black flies (Simulium flies)

Here’s a couple of others for those who just can’t get enough of insect orders (yes, they’re optional)

8. Megaloptera

DOBSONFLY LARVA

9. Lepidoptera

AQUATIC MOTH

Stop here for today

VI. Metamorphosis

A. Incomplete metamorphosis

B. Complete metamorphosis

Mystery picture

Mystery picture 2

VII. Modifications for Aquatic Life

I. Air Breathing (Aeropneustic)

A. Regular insect-style breathing with spiracles on the abdomen

For insects that never submerge

B. Siphon a snorkel / breathing tube

II. Air Trapping A. Abdominal air bubble

B. Plastron: tiny hairs on insect’s surface that trap air

C. Diving bell

III. Water breathing (Hydropneustic) A. Using gills

1. Three gills at tip of abdomen damselfly nymph

2. Single gills found under the legs stonefly nymph

3. a. Seven pair of abdominal gills Mayfly nymphs

4. Gills inside the abdomen dragonfly nymph

(extra) Lateral filaments on the abdomen of larvae Whirligig beetle larva

B. Bright red hemoglobin, allows diffusion Midge larva

B. Movement

Mystery picture 2

Skaters: surface tension, oil secretion, hairs water strider

2. Clingers: flat bodies with little resistance, suckers or claws; water pennies

3. Climbers: long legs holding plant stalks; dragonfly & damselfly nymphs

4. Crawlers: on solid surfaces, find crevices; stonefly & mayfly nymphs

5. . Burrowers: dig into substrate; midge larvae

6. Swimmers: wiggle entire body fishlike; mayflies, mosquitoes

7. Rowers: use oar-like modified legs

Also water boatman

C. Particular modifications

1. Ripple effect

2. FOUR EYES!

3. Oars bristles on legs

4. Flattened body

Are there any MARINE INSECTS?

What do these numbers mean? Estimated number of insect species Described insect species Known aquatic species Insects that live on the open ocean (oceanic species) At LEAST 3 million ± 850,000,000 30,000 5

Why are there so few insects living in the ocean Why are there so few insects living in the ocean? Is it because of the salty water?

No. There are aquatic insects that have adapted to salty environments (like these salt marsh mosquitoes.)

Alkaline flies of Mono Lake (also called brine flies)

Intertidal rove beetle; wait in burrows till tide’s out

Seaweed flies; maggots eat rotting seaweed

But why do so few live out in the ocean?

2 reasons:

1. Crustaceans got there first

http://www.livescience.com/48663-insect-family-tree-evolution.html

2. They make good fish food:

But crustaceans survive

So why don’t insects just dive deeper?

The insect’s respiratory system is different from that of crustaceans

Insects can’t go deep, crustaceans can