Download General Chracters Od Insects - GCG-42

The insects abound in all habitats –
water land and air. Most of them
are free-living, but some are
parasites on animals and plants.
A few are colonial and social. The
class Insecta is the largest class of
the animal. Every fifth organism on
this earth is an insect.
Characteristics of class-Insecta
some characteristics of Insecta are
Body :Divided in to three distinct regions
Head , thorax and abdomen
Head :
One pair of antennae (olfactory)
One pair of compound eyes and many simple eyes called ocelli
Mouthparts variously modified for piercing and sucking, siphoning,
sponging,
biting and chewing
Thorax :Three segmented
Each segment with a pair of legs
Two pair of wing on meso and metathorax
Abdomen :Consist of eleven or fewer segments ,
with out appendages Except a pair of
anal cerci on last segment
Gential opening at posterior
end of abdomen
Classification of insecta
Class inseta is divided into two sub classes
Apterygota ( primitive wingless insects)
Pterygota ( winged and secondarily wingless
insects)
The sub class Pterygota is divided in two division
Exopterygota – insects with simple meta
mortphosis with out pupal stage
Endopterygota – insects with complete meta
morphosis including a pupal stage
Apterygota
Order Thysanura
Bristletails
Order Diplura
Diplurans
(Two-pronged Bristletails)
Order Protura
Proturans
Order Collembola
Springtails
Exopterygota
•
•
•
•
Order
Ephemeroptera
Odonata
Orthoptera
• Dictyoptera
• Phasmida
• Dermaptera
Mayflies
DragonfliesandDamselflies
Grasshoppers, Locusts
and Crickets
CockroachesandMantids
Stick insects and Leaf
insects
Earwigs
order Isoptera
Plecoptera
Psocoptera
Termites
Stoneflies
Psocopterans
(Psocids,Booklice)
Chewing lice
Sucking lice
Mallophaga
Anoplura
(Siphunculata)
Thysanoptera
Thrips
Hemiptera
suborder Heteroptera Bugs
suborder Homoptera Cicadas, Hoppers,
Psyllids, Whiteflies,
Aphids, and Scale insects
Endopterygota
Order Neuroptera
Alderflies, Dobsonflies, Fishflies,
Snakeflies, Lacewings, Antlions, and
Owlflies
Order Coleoptera
Order Strepsiptera
Order Mecoptera
Order Trichoptera
Beetles
Twisted-winged parasites (Stylopids)
Scorpionflies
Caddisflies
Order Lepidoptera
Order Diptera
OrderSiphonaptera
Butterflies and Moths
True Flies
Fleas
OrderHymenoptera Sawflies, Ichneumons, Chalcids, Ants,
Wasps, and Bees
Thysanura
Include silver fish
Soft bodied
No wings
Body covered with silver scales hence silver fish
Chewing moth parts and feed on starch
Metamorphosis absent
• Important characters of the common orders of class insecta
• Collembola
•
•
•
•
•
•
Include Spring tails
Soft bodied insect
No wings
Chewing mouth parts and feed on decaying plant and fungis
Furcula present at end of abdomen that helps in leaping like a spring
Metamorphosis absent
Orthoptera
Includegrasshopper ,Cricket
Forewings leathery called tegmina
Hindwing thin veined
Chewing mouth parts – herbivorous
Metamorphosis Gradual
(Egg,nymph,adult)
Metalegs enlarged for jumping
Dictyoptera
Include cockroach and mantis
Forewings leathery called tegmina
Hindwing thin veined
Chewing mouth parts carnivorous , omnivorous
Metamorphosis gradual
Prolegs large grasping ( mantis)
Phasmida
Include stick insect, leaf insect
Body modified to mimic twigs or leaves
Forewing leathery , Hind wings thin
Mouthparts chewing –herbivorous
Metamorphosis gradual
Dermaptera
Include earwigs
Forewing short leathery veinless
Hindwings large semicircular radially veined
Mouthparts chewing –feed on insects
Metamorphosis gradual
Cerci unjointed and form forceps
Plecoptera
Include stoneflies
Forwings thin narrow
Hindwings thin broad
Chewing mouthparts- feed on insects
Incomplete Metamorphosis (Egg, Naiad, Adult)
Isoptera
Include Termites
Both wings thin and veined
Chewing mouth parts – feed on wood
Gradual Metamorphosis
Odonata
Include dragon and damsel flies
Huge eyes
Both wing thin , alike , richly veined
Chewing mouth parts – feed on mosquito
Incomplete Metamorphosis
Ephemeroptera
Include may flies
Both wings thin and large
Chewing mouthparts ( Naiad feed on greenvegetation
Metamorphosis incomplete
Abdomen has very long two or three terminalfilaments
Mallophaga
Include Biting lice
Wings absent , Eyes reduced
Chewing mouthparts –feed on fragments of feather
Metamorphosis gradual
Anoplura
Include sucking lice
Wing absents
Piercing and sucking mouthparts
Metamorphosis gradual
Tarsi one jointed with single grasping claw
Hemiptera
Include Bugs and its allies
Piercing and sucking
mouthparts that from a beak
Large compd. Eyes
Basal portion of forewing thick
and apex is thinner and
transparent
Gradual Metamorphosis
Suborder Homoptera –
Include cicadas , aphids, scale insects
Membranes of fore wings typically
translucent
Beak arises from posterior portion of head
Head has tentorium
Plant feeders
Suborder Heteroptera :Include Bugs
Base of front wings are thinkened and apex is
membranous
Beak arises from front end of head
Head without tentorium
Many are predacious
Neuroptera
Include Antlions, lace wings, alder flies
Look like dragonflies but have knobbed antenna
Wing thin and alike having many veins and crossveins
Chewing mouth parts –mostly predacious
Complete Metamorphosis (Egg, Larva, Pupa, adult)
Alder fly
Coleoptera
Include Beetles and weevils
Large prothorax
Forewing thick , veinless called elytra
Chewing mouthparts feed on plants, grains
Metamorphosis complete
Hymenoptera
Include bees, wasps,ants,
First abdominal segment is fused with the
thorax and next two segments are
constricted to from a narrow pedicel
Wings thin, locked during flight with hamuli
Chewing,lapping sucking mouthparts
Metamorphosis complete
Diptera
Include flies , Mosquitoes
Forewings are veined , membranous and
transparent
Hind wings reduced to small knobs –Halteres
Mouthparts sponging or piercing and sucking type
Metamorphosis complete
Lepidoptera
Include butterflies and moths
Body soft covered with scales ( Modified setae)
Antennae long tapering ( Moth ) Knobbed ( Butterfly)
Both wings membranous covered with powdery scales
Mouthparts siphoning in adults and chewing in caterpillars
Metamorphosis complete
Siphonaptera
Include ectoparasitic fleas
Body laterally compressed
Antennae short
Compound eyes absent , ocelli
present
Wings absent
Mouthparts piercing and sucking
Metamorphosis complete