Insect Hunters

Insect BustersWho Ya Gonna Call?

Hexapoda• Six-legged• 30 million species (Triplehorn & Johnson)• All habitats• 31 orders (30 in N.A.)• Typically classified by wing characteristics

– Ptera

• Metamorphosis– Complete (egg, larva, pupa, adult)– Incomplete (egg, nymph/naiad, adult)

Ephemeroptera

• Mayflies• Soft-bodied• 2 or 3 long, threadlike

tails• Large, triangular front

wings with small, rounded hind wings

• Small, bristle-like antennae

• Live one to two years in water in nymph stage and one to two days in adult stage

Orthoptera

• Plant feeders- pests to cultivated pests

• Elongated body-may or may not be winged

• 2 pairs of wings

Forewing (tegmina), Hind wing larger & membranous

• Larger hind legs

Orthoptera

• Mandibulate• Metamorphosis is

simple• Some of the best

known insect singers • Grasshoppers &

Crickets (cockroaches previously)

Blattodea

• Shares many features of grasshoppers & crickets

• Oldest winged insect• Flattened oval bodies• Long, swept back antennae• Have wings• Females lay egg packets• Simple metamorphosis• Flourish anywhere there is

sufficient food & warmth

Hemiptera – “True Bugs”• 2 pair of wings,

– front wing is thick and leathery, tips are membranous;– hind wings are membranous

• Visible triangle called scutellum • Sucking and piercing mouthpart • Incomplete metamorphosis• Terrestrial and aquatic habitats• Reduvidae - transmit Chagas Disease

Homoptera

• Includes: Cicadas, Hoppers (tree and leaf), Spittlebugs, Whiteflies, and Aphids

• There are approximately 45,000 species worldwide – 6,000 of which are in N. America

• They are all plant feeders• Metamorphosis is simple in

homopterans

Homoptera

• Methods of reproduction:– Sexually: Male and Female mate (Cicadas

and Leafhoppers)– Parthenogenetically: All Female, no mating

• Aphids produce many billions in lifetime

• Characteristics:– Have sucking, beaklike mouthparts that arise

far back beneath the head– Wings are uniformly membranous

Neuroptera

• Order name means “nerve wings” due to the net of crisscrossing veins

• Beneficial because they help control destructive insects

• Have many veins in 4 transparent wings and an especially wide border of cross veins on the front margin of the forewings

• There are about 4,500 species worldwide, and 338 in N. America

Neuroptera• Includes: Lacewings, Mantidflies,

Antlions, and Spongillaflies• Characteristics:

– They all have 2 pairs of wings – similar in size and have elongate oval shape

– When at rest, the wings are held “rooflike” over the body. In use, they beat in a poorly coordinated fashion

– Their mouthparts are adapted for chewing

– Antennae may be threadlike, clubbed or toothed (like a comb)

– Most species have large compound eyes

Neuroptera

• Neuroptera go through complete metamorphosis:– Larvae do not resemble the adults– Most larvae are predators– All larvae have large, sickle-shaped

mandibles that are used to seize and eat smaller insects or sponges

– Pupation occurs in silken cocoons spun in sand or soil

Coleoptera

• Common Name: Beetles• Largest Order of Insects• Elytra – armor-like

forewings cover flight wings

• Segmented legs and antennae

• Chewing mouthparts with well developed mandibles (jaws)

• Simple brain with many sense organs

Diptera• Identification

– One pair of membranous wings– Vestigial second pair of wings (halteres) – Large compound eyes – Most have sucking mouth parts

• Complete metamorphosis– Aquatic and terrestrial larva

• maggots

Diptera

• Diverse group – inhabiting numerous niches

• Importance– Important food source

for many animals – Parasites– Vectors for disease

• Malaria, African Sleeping Sickness, West Nile, River blindness

Lepidoptera

Lepidoptera

Moths and Butterflies

Complete metamorphosis– Egg– Larvae (Caterpillar)- destructive– Pupa (adult)- cocoon or chrysalis– Adult

• Chewing mouthparts in caterpillar and sucking, coiled mouthparts in the adult

• Scales on the wings

Lepidoptera• Moths• No clubs on antennae• Appear more at night• Feathery antennae that

pick up pheromones released by female

• Butterflies• 120,000 Species• Clubbed antennae• Appear more in the day• Slimmer bodies, more

colors

Tricoptera

• Caddisfly• “hair wings”• Resemble moths

– No proboscis, instead have pronounced palps– Very long antennae– Most have no scales on wings– Aquatic larvae, instead of terrestrial caterpillars

• Make case of leaves, twigs, sand grains• Pupae emerge, swim to shore, then adult emerges

Odonata• Dragonflies and Damselflies• Small antennae• Long legs- not suitable for walking• Chewing mouthparts• Nymphs are aquatic, adults are found near water• Highly predaceous on flying insects

Hymenoptera

• Made up of sawflies, wasps, ants and bees

• Probably most beneficial of entire insect class. Contains parasites, predators and most importantly, pollinators (bees)

• Great diversity of habits and behaviors.

• Most are in social organizations (wasps, bees and ants)

Hymenoptera• Ovipositor is tube used to lay eggs.• In most Hymenoptera have a modified

ovipositor; a sting• Only females can sting• The sex of Hymenoptera is determined by

fertilization.

Hymenoptera

Interesting Fact:

*Bees die when they sting because they have barbs on their stingers that restrict the stinger from leaving the skin; therefore, when the bee flies away she is literally pulling her guts out.

*The queen’s stinger has no barbs so she is able to sting and not die.

Isoptera– Termites– “same wing”– Commonly called “white ants” WRONG!

• Hind wings are the same size as forewings• Soft, light-colored body• No petiole• Antennae are not elbowed• Sterile casts are females

only from fertilized eggs

– Caste system• Reproductives• Workers• Soldiers