Common Insect Orders

Adapted from Berkeley Natural History Museums lesson “A Quick Way to Identify Common Insect Orders”

Insects are the most species-rich group of organisms on earth as indicated in this species-scape. The size of the organism reflects the number of described species.

Parts of an insect

Parts of an insect

Head Thorax Abdomen

Parts of an insect

Head Thorax Abdomen

3 pairs of legs

Parts of an insect

Head Thorax Abdomen

3 pairs of legsWings and legs on thorax

Important areas to study to identify common insect orders

Head Thorax Abdomen

3 pairs of legs

Mouthparts:Chewing

mandibles

mandibles

Mouthparts:

Piercing

Sucking

Sponging-sucking

Coiled

Orthoptera (grasshoppers, crickets, katydids) Greek "ortho" = straight, "ptera" = wing

Spot ID• Jumping legs• parallel-sided structure

of front wings

Orthoptera (grasshoppers, crickets, katydids)

Greek “orthos” = straight, “pteros” = wing

Orthoptera (grasshoppers, crickets, katydids)

Orthoptera (grasshoppers, crickets, katydids)

Spot ID• Jumping hind legs

Orthoptera (grasshoppers, crickets, katydids)

Spot ID• Jumping hind legs• Some with ovipositor at hind

end

Coleoptera (beetles)Greek “koleos”= sheath, “ptero”= wing

Coleoptera (beetles)

Coleoptera (beetles)

Spot ID• Chewing mouthparts

Coleoptera (beetles)

Spot ID• Chewing mouthparts• Forewings (elytra)

form hard shell covering hindwings

Lepidoptera (butterflies, moths)Greek “lepido”= scale, “ptero”= wing

Lepidoptera (butterflies, moths)Greek “lepido”= scale, “ptero”= wing

• Coiling-sucking mouthparts

Lepidoptera (butterflies, moths)Greek “lepido”= scale, “ptero”= wing

• Coiling-sucking mouthparts• Four wings covered with scales

Diptera (flies)Latin “di”= two, “ptero”= wing

Diptera (flies)Latin “di”= two, “ptero”= wing

Spot ID• Two wings

Diptera (flies)Latin “di”= two, “ptero”= wing

Spot ID• Two wings

– Hind wings reduced to halteres

Diptera (flies)Latin “di”= two, “ptero”= wing

Spot ID• Two wings

– Hind wings reduced to halteres

• Sponging-sucking mouthparts– Except mosquitoes

and some others that pierce skin

Diptera (flies)Latin “di”= two, “ptero”= wing

Hymenoptera (bees, wasps, ants)

Greek “hymen”=membrane, “ptero”=wing or

Hymen, the Greek god of marriage because the forewing & hindwings are joined

together with small hooks

Hooks not shown

Hymenoptera (bees, wasps, ants)

Hymenoptera (bees, wasps, ants)Spot ID• Chewing mouthparts

Hymenoptera (bees, wasps, ants)Spot ID• Chewing mouthparts• Four membranous wings

Hymenoptera (bees, wasps, ants)Spot ID• Chewing mouthparts• Four membranous wings• Waist often constricted

Hymenoptera (bees, wasps, ants)Spot ID• Chewing mouthparts• Four membranous wings• Waist often constricted• Females with ovipositor or

stinger at end of abdomen

Hemiptera (true bugs, also sometimes called Heteroptera)

Greek “hemisys” = half, “ptero” = wing

Hemiptera (true bugs)

Greek “hemisys” = half, “ptero” = wingSpot ID• A beak: piercing-sucking mouthparts

Hemiptera (true bugs)

Greek “hemisys” = half, “ptero” = wingSpot ID• A beak: piercing-sucking mouthparts• Forewings covering hindwings

– Wing half membrane, half thickened

Homoptera (hoppers, aphids, scales, cicadas)

Greek “homo” = uniform, “ptero” = wingSpot ID• A beak: piercing-sucking mouthparts• Forewings covering hindwings

– Wings all membranous

Homoptera (hoppers, aphids, scales, cicadas)

Greek “homo” = uniform, “ptero” = wingSome entomologists now combine Order

Homoptera with Order Hemiptera because the DNA has been found to be similar. In this case, Homoptera would be considered a suborder.

Dermaptera (earwigs)Greek “derma” = skin, “ptero” = wing

Dermaptera (earwigs)Greek “derma” = skin, “ptero” = wing

Spot ID• Long skin-like hindwings folded

under very short forewings

Dermaptera (earwigs)Greek “derma” = skin, “ptero” = wing

Spot ID• Long skin-like hindwings folded

under very short forewings• Pinchers off end of abdomen

Odonata (dragonflies, damselflies)

Greek “odon” = tooth (referring to teeth on their mandibles)

Odonata (dragonflies, damselflies)

Odonata (dragonflies, damselflies)

Spot ID• Long slender wings

Odonata (dragonflies, damselflies)

Spot ID• Long slender wings• Long thin body

Isoptera (termites) Greek "iso" = equal, "ptera" = wings

Spot ID• Pale, elongate body • 2 pairs of membranous

wings of equal length only present in reproductives and shed after mating

• Mandibulate (chewing) mouthparts

• Antennae about the same length as the head

• Sometimes now classified with Blattodea because their DNA suggests that they are specialized roaches

Blattodea (roaches)Latin “blatta” = cockroach

Blattodea (roaches)

Blattodea (roaches)

Spot ID• Flat

Blattodea (roaches)

Spot ID• Flat• Spiny legs

Blattodea (roaches)Also called Blattaria, Greek “Blatta” = cockroach

Spot ID• Flat• Spiny legs• Long antennae

Neuroptera (ant lions, lacewings, mantidflies)

Greek "neuron" = nerve and "ptera" = wingsSpot ID• four membranous net-

veined wings• forewings and

hindwings about the same size

Neuroptera (ant lions, lacewings, mantidflies)

Greek "neuron" = nerve and "ptera" = wingsSpot ID• Larvae have elongated

mandibles adapted for piercing and sucking

• Oliver the Owlfly larva is an example

• Antlion larvae (doodlebugs)

Mantodea (praying mantises)Greek “mantis” = prophet

Spot ID• two grasping, spiked

forelegs often held in “praying” position

• Triangular, swiveling head with large compound eyes

Phasmatodea (walking stick insects)Also Phasmida, Greek “phasm” = phantom

Spot ID• cylindrical stick-like

body or flattened, leaflike shape

• long, slender antennae• sometimes have wings

Thysanura (silverfish, bristletails)Greek "thysano-" = fringed, "ura" = tail

Spot ID• three long caudal (tail)

filaments• Silverfish are so called

due to the silvery glitter of the scales covering their bodies

• flattened bodies, may be elongated or oval in shape

Ephemerida (mayflies) Also Ephemeroptera, Greek "ephemera"

=short-livedSpot ID• delicate bodies and

gauzy, fragile wings• two or three long

threads (caudal filaments) at end of abdomen

• Adults have no functional mouthparts

Plecoptera (stoneflies)

Greek "pleco" = braided, "ptera" = wingSpot ID• complex venation of two

pairs of wings, which are membranous and fold flat over the back

• legs each end in two claws

• long, multi-segmented antennae

Mecoptera (scorpionflies) Greek “meco-” = long, “ptera” = wings Spot ID• abdomen is cylindrical,

and typically curves upwards in the male, superficially resembling the tail of a scorpion

• wings are narrow in shape, with numerous cross-veins

Trichoptera (caddisflies)Greek “trich” = hair, ptera = wing

Spot ID• small moth-like with

two pairs of hairy membranous wings

• Aquatic larvae, adults usually found near aquatic habitats

Siphonaptera (fleas) Greek "siphon“ = tube or pipe, "aptera" =

wingless Spot ID• Wingless (adaptation to

ectoparasitism) • 1-10mm long • Mouthparts are sucking and

piercing • Hind legs are enlarged for

jumping • Laterally flattened

Thysanoptera (thrips)Greek "thysano-" = fringed, “ptera" = wing

• Very small insects with a range of 1/32 to 1/8 inch in length

• Feed on plants, considered crop pest

Some Common Insects