What is an insect? air breathing animal hard jointed exoskeleton in the adult, a body divided into three parts  the head with one pair of antennae  the thorax which carries three pairs of legs and usually two pairs of wings  and the abdomen which contains the guts and reproductive organs

Head The head is the anterior of the three body regions of an adult insect It bears the eyes (usually a pair of compound eyes) Antennae Mouthparts

Chewing type  grasshoppers  Beetles Sucking mouthparts shaped like stylets  Bugs  aphids Sucking shaped like a coiled tongue  Butterflies  moths LabrumMandiblesMaxillaeLabium

Antennae detect odors tactile (touch) organs variable in form and size

Thorax middle of the three body regions of an adult insect composed of 3 segments 3 pairs of legs (one on each segment) usually 2 pairs of wings Some insects have only 1 pair of wings.

Legs Adult insects have 6 legs Each of the segments of the thorax bears 1 pair of legs The legs are segmented Often the last segment of the leg bears a small claw In some insects, the legs are specially adapted for jumping.

Wings Most adult insects have 2 pairs of wings some (for example flies) have only 1 pair of wings Usually the wings are membranous in some insects they can be leathery or hard Sometimes the wings bear hairs or small scales.

Abdomen The abdomen is the posterior of the three body regions of an adult insect It is composed of 11 segments The abdomen bears the external genitalia In female insects these consist of an ovipositor.

Metamorphosis of Insects Several stages in the change from egg to adult Instars are stages of larval development Four kinds of metamorphosis  Without  Gradual  Incomplete  Complete

Gradual/Incomplete Metamorphosis

Gradual Metamorphosis In gradual metamorphosis, the nymphal stages resemble the adult except that they do not have wings and the nymphs may be colored differently than the adults

Complete Metamorphosis

Wings develop internally during the larval stages. The larval stages look quite different from the adult Between the last larval stage and the adult stage there is a pupal stage which usually is inactive.

Complete Metamorphosis

Insect Orders 32 Orders We are studying 20 orders

Endopterygota endo = inside; pterygot = little wing Insects with complete, complex metamorphosis in which the wings develop internally  Coleoptera – beetle  Diptera – flies  Hymenoptera – Ants, Bees & Wasps  Lepidoptera – Butterflies and Moths  Neuroptera - Lacewings

Exopterygota exo =outside; pterygion=little wing Winged insects with incomplete metamorphosis  Dermaptera – earwigs  Hemiptera – true bugs  Homoptera – cicadas, aphids, spittlebugs, leafhoppers, whiteflies  Orthoptera – crickets and grasshoppers  Thysanoptera – thrips

Endopterygota Inside little wing Complete metamorphosis

Coleoptera kole-ee-OP-tera the largest group of insects (25,000 species in No. America) beetles and weevils (snouted beetle) 2 pairs of wings  Outer hardened  Inner membranous chewing mouthparts (both adults and larvae) Larvae: head capsule, 3 pairs of legs on thorax, no legs on abdomen complete metamorphosis

Coleoptera Colorado Potato Beetle Ground Beetles Ips Beetle Japanese Beetle Ladybird Beetles

Diptera DIP-tur-ah gnats, mosquitoes, and true flies a single pair of membranous wings sucking or piercing mouthparts Larvae are legless (maggots) complete metamorphosis

Diptera Aphid Predator Midge Leafminer Surphid Fly Tachinid Fly Feeding habits vary  Scavengers (House flies)  Blood feeders (Mosquitos)  Plant galls (gall midges)  Predators (flower files)  Aquatic

Hymenoptera hi-men-OP-tare-ah sawflies, ants, bees, and wasps 2 pairs membranous wings chewing or chewing-lapping mouthparts Larvae with no legs complete metamorphosis

Hymenoptera Leaf-cutter bees Parasitic wasps Pearslugs

Lepidoptera lep-ih-DOP-ter-ah moths, skippers, and butterflies scale-covered wings coiled siphoning mouthparts to feed on nectar Larvae with chewing mouthparts and are voracious feeders Larvae generally have legs on the abdomen as well as thorax complete metamorphosis

Lepidoptera Army cutworms Borers Cabbage loopers Codling moths Pine Tip Moth Pinon Pitch Mass Borer Tomato Hornworms

Neruoptera nur-OP-ter-ah Lacewings, antlions, snakeflies Insect predators, many are aquatic 2 pairs of membranous wings chewing mouthparts complete metamorphosis

Exopterygota Outside little wing Incomplete/gradual metamorphosis

Dermaptera dur-MAP-ter-ah Earwigs short, hardened wing covers chewing mouthparts pincer like abdominal cerci gradual metamorphosis

Hemiptera he-MIP-tare-ah true bugs 2 pairs of wings;half leathery/half membranous forewings Piercing - sucking mouthparts gradual metamorphosis Both adults and nymphs are damaging

Hemiptera Boxelder Bugs Minute Pirate Bug Spined Soldier Bug Squash Bugs

Homoptera ho-MOP-tare-ah Cicada, aphids, spittlebugs, leafhoppers and whiteflies  a jointed beak  but in which the fore-wings are either wholly membranous or wholly leathery  Winged and unwinged forms

Homoptera Aphids Cooley Spruce Gall Agelid Leafhopper Scale Wooly Apple Aphids Phloem feeders Vector many pathogens

Orthoptera oar-THOP-tera made up of the grasshoppers, grouse locusts, katydids, crickets, and mole crickets, praying mantid  leathery forewings  chewing mouthparts  Hind legs generally enlarged for jumping  gradual metamorphosis

Thysanoptera thigh-san-OP-ter-ah Thrips  2 pairs of fringed wings  Small soft-bodies insects  Rasping-sucking mouthparts  Found on flowers or leaves of plants  Mix of gradual and complete metamorphosis

Insect Key With Wings  One Wing  Two Wings Without Wings bioresearch.co.uk/key.htm