Complete Metamorphosis Part 2

Order Mecoptera: Scorpionflies

• Predators and scavengers

• Complete metamorphosis

• Common name based on scorpion-like shape of male abdomen and gentalia

• No functional stinger

Scorpionfly Courtship

• Males give female nuptial gifts

• Ball of his own saliva

• Dead arthropod

• Why?

  • Females can be aggressive

  • Gift helps keep male safe

  • Wants to impress female

• Females prefer males with bigger gifts

• Male may gather up leftovers for next female

Lepidoptera Larvae=Caterpillars

• Herbivores

• Thorax with 6 true legs

• Abdomen with fleshy legs called prolegs

Stinging Caterpillars

• Hairs for defense

• Flannel Moth Caterpillar

  • Recover in a day but extremely painful

  • Feels like a broken arm or being hit by a hammer

• Io Moth Caterpillar

  • Sting painful but harmless unless severe allergic reaction

• Saddleback Caterpillar

  • Similar to bee sting

Woolly Worm

Can’t actually predict winter weather

Lepidoptera Pupae

• Many moths spin silk cocoon

• Butterflies and some moths do not spin cocoon

Lepidoptera: Adults

• Siphoning mouthparts

• Drink nectar from flowers

Butterflies

• Knobbed antennae

• Fly during day

• Bright colors

Moths

• Bushy or pointed antennae

• Fly at night

• Dull, dark colors

Corn Earworm

• Can just cut off the damaged part of the ear

• Farmers spray sweet corn fields ever 2-3 days

Eastern Tent Caterpillars

• Outbreaks every several years

• Mare Reproductive Loss Syndrome: 2001

Order Siphonoptera: Adult Fleas

• Piercing-sucking mouthparts

• Blood-feeding parasites

• Secondarily wingless

• Ancestors had wings but didn’t need them so lost over time

• Complete metamorphosis

Flea Larvae

• Live in the sleeping place of the host

• Don’t feed on host

• Feed on adult flea dried blood

Flea Pupa

• Make a silken cocoon that’s resistant to insecticides

• Vibrations of host movements can trigger emergence

Adult Fleas can harm hosts by…

• Biting and causing irritation

• Transmitting tapeworm parasites

  • Dog or cat swallows flea that contains young stage of the tapeworm

• Transmitting diseases

The Plague

Caused by fleas

Biological Warfare using Fleas

• World War II

• Japan developed bombs filled with plague-infested fleas

• Tested it in two cities in China and led to plague outbreaks

  • 200,000 Chinese people died as a result of Japan’s biological agent program

• Plan for operation called “Cherry Blossoms at Night” would have released fleas over California but plan was never executed

Order Diptera: True Flies

• Only 1 pair of wings

  • No hind wings

• 1 pair of Halteres

  • Hind wings evolutionarily modified to form tiny organs which sense balance during flight

• Mouthparts of adults vary by species

Diptera Larvae-Maggot

• No legs

• Mouth hooks

• Parasites, herbivores, scavengers, filter feeders in water

• Some species used in medicine

Good Dipteras

• Maggots can be important decomposers

• Some predators or parasitoids of insect pests

• Some pollinate plants

Bad Dipteras

• Largest number or species that spread pathogens causing animal diseases

• Some damage plants

• Some feed on blood/tissues of animals

Crane Fly (“mosquito hawk”)

• Look like big mosquitos

• Don’t bite humans or eat mosquitos

• Barely eat as adults

Mosquito

• Piercing-sucking mouthparts

• Females need blood for egg development

  • Males don’t bite

• Heat, movement, exhaled carbon dioxide, body scent attract them

• Transmit disease

• Deadliest insect in the world

Horse and Deer Flies

• Females are vicious, painful biters

• Cut skin with knife-like mouthparts and suck blood for several minutes

• Feed on blood of cattle, horses, dogs, humans

Flower flies/Hover flies (“sweat bees”)

• Visit flowers to drink nectar

• Similar appearance as bees and wasps but no stinger

House Flies

• “Filth Flies”

• Feed and lay eggs on garbage, manure, carrion, and can then contaminate human foods and food preparation surfaces by landing on them

• Can spread food poisoning and dysentery

Do house flies vomit when they land on our food?

• Have sponging mouthparts

• “Spit” saliva on solid food to begin to liquefy and digest it so they can suck it up

• Germs likely come from their feet