Class: Insecta

Order: Thysanura(silverfish), and Archaeognatha(bristletail) are apterygota. Pterygota is divided into paleoptera and neoptera.

order: Odonata and order: Ephemeroptera are paleoptera. Paleoptera has a wing structure which can not be folded at rest.

Neoptera is further divided into orthopteroidea, plecopteroid, paraneoptera(hemipteroidea), endopterygota. Endopterygota is divided into neuropterida, hymecopteroidea, amphiesmenoptera, antiliophora([4]).

Arnett[5] has divided exopterygota into polyneoptera, paraneoptera, acercaria. Acercaria is further divided into psocodea and condylognatha. According to Arnett, Blattodea and Mantodea are classified as order: Dictyoptera, and Phthiraptera is named as order: Anoplura. Mallophaga(chewing lice) is an order. Table [*] lists orders of exopterygota.

Table 4: Orders of Exopterygota


Order 	Insects

Order: Orthoptera 	grasshoppers, crickets, roaches

Order: Blattodea 	roaches

Order: Mantodea 	mantids

Order: Isoptera 	termites

Order: Plecoptera 	stoneflies

Order: Dermaptera 	earwigs

Order: Embioptera 	embio(lively), web spinners

Order: Phasmetodea 	 

Order: Grylloblattodea 	walking sticks

Order: Zoraptera 	zor(pure), zorapterans

Order: Psocoptera 	psoco(rub), book lice

Order: Phthiraptera 	sucking lice

Order: Thysanoptera 	thrips

Order: Hemiptera 	bugs,cicadas, aphids, leafhoppers

Wings of endopterygota develops in imagninal disc. Table [*] shows orders of endopterygota.

Table 5: Orders of Endopterygota


Order 	Insects

Order: Neuroptera 	lacewings, dobsonflies

Order: Megaloptera 	 

Order: Raphidioptera 	snakeflies

Order: Coleoptera 	beetles

Order: Strepsiptera 	strepsi(turning), twisted

Order: Mecoptera 	moco(long) scorpionflies

Order: Diptera 	true flies

Order: Siphonaptera 	fleas

Order: Trichoptera 	caddisflies

Order: Lepidoptera 	butterflies, moths

Order: Hymenoptera 	bees, wasps, ants

Malpighian tubules are the bifercated GI of an insect.