Insect Identifier - Part 3 - Insects with Modified Wings

Abdomen with forceps-like cerci

Earwigs
Elongated insects with chewing mouthparts; forewings reduced to very short leathery tegmina devoid of veins; hindwings semicircular with radially disposed veins, folded fanwise and then transversely; many species wingless; cerci unjointed and modified to form heavily sclerotized forceps.   Order Dermaptera
Abdomen lacks forceps-like cerci.  Continue below.

Abdomen lacks forceps-like cerci

Mouth parts for sucking
Front wings nearly always thickened at base
  assassin bug water bug Bark bug Shield Bug
True bugs
Mouthparts adapted for piercing-sucking, with slender segmented beak arising from front of head; basal portion of front wing (called a hemelytron) thickened and leathery, with tip membranous; hindwings entirely membranous; wings at rest held flat over abdomen with membranous tips of front wings overlapping; ocelli present or absent; compound eyes usually well developed. Order Hemiptera
Front wings of uniform texture. 

Cicada Leafhopper Aphid
Cicadas, hoppers, whiteflies, aphids, scale insects
Plant feeders; mouthparts adapted for sucking; beak arises from back of head; wings, when present, usually number four; front wings with uniform structure, either membranous or slightly thickened; wings at rest usually held roof-like over body; male scale insects with only 1 pair of wings; ocelli present or absent; compound eyes usually well developed.  Order Homoptera 

Mouth parts for chewing 

Front wings with veins
Grasshopper Cricket Katydid
Mantis Walking Stock Cockroach
Grasshoppers, Crickets, Katydids, Mantids, Walkingsticks, & Cockroaches 
Although fixed physical features such as wing characteristics are all technically the same, there is a great deal of variety in actual apperance.  Order Orthoptera 
Front wings without veins
Carrion Beetle Firefly Lady Bug Weevil
Beetles
Minute to large in size; modified forewings are horny or leathery (elytra), usually meet to form a straight middorsal suture; hindwings membranous, folded below elytra, often vestigial or absent; mouthparts adapted for chewing; prothorax large and mobile, mesothorax much reduced; larvae varied (campodeiform and eruciform), pupae exarate, without articulated mandibles.  Order Coleoptera