Abdomen: the third or posterior division of the body; consists normally of nine or ten apparent segments; bears no functional legs in the adult stage. Antennae: the paired, segmented sensory organs on each side of the head, commonly called horns or feelers. Cercus/cerci: a tail-like appendage (generally paired) of the tenth abdominal segment, usually slender, filamentous and segmented. Cocoon: a covering, composed partly or wholly of silk or other viscid fibre, spun or constructed by many larvae as a protection to the pupae. Compound eye: compound means made up of many similar or dissimilar parts. A compound eye is an aggregation of separate visual elements known as ommatidia, each of which corresponds with a single facet of the cornea; the large lateral eyes of most insects. Coxa: the basal segment of the leg, by which the leg is articulated (attached) to the body. Elytron/elytra: the anterior leathery wings of beetles, serving as coverings to the hind wings, commonly meeting in a straight line down the middle of the body in repose. Halter/halteres: the poisers or balancers. Capitate moveable filaments in Diptera (true flies), situated one on each side of the thorax and representing the hind wings. Hemielytron/ hemelytra: The anterior wing in the Heteroptera (suborder of true bugs), the basal (top) half of which is thickened and the apical (apex or tip) membranous. Mandibles: the first pair of jaws in insects, stout and tooth-like in chewing insects, needle- or sword-shaped in piercing-sucking insects; the lateral upper jaw of biting insects. Maxilla: the second pair of jaws in a mandibulate insect. Mesothorax: the second or middle thoracic segment which bears the middle legs and the anterior wings. Metamorphosis: the series of changes through which an insect passes in its growth from the egg through the larva and pupa to the adult; complete when the pupa is inactive and does not feed; incomplete when there is no pupa or when the pupa is active and feeds. Metathorax: third thoracic segment which bears the hind legs and second pair of wings; variably distinct, sometimes closely united with the mesothorax and sometimes appearing as part of the abdomen. Ocellus/ocelli: the lateral simple eyes in larvae which detect only light and dark; not image forming. Ovipositor: the tubular or valved structure by means of which the eggs are placed; usually concealed, but sometimes extended far beyond the end of the body. Proboscis: any extended mouth structure; usually applied to the extensile mouth of the Diptera (true flies), the beak of the Hemiptera (true bugs); sometimes to the tongue of the Lepidoptera (butterflies and moths); and rarely, to the mouth of long-tongued bees. Prothorax: first thoracic segment; it bears the anterior legs but no wings; when free, as in Coleoptera (beetles) and Heteroptera (suborder of true bugs), it is usually referred to as "thorax". Pupa/Pupae: the resting inactive stage of complete metamorphosis, between larva and adult. Tarsus/tarsi: the foot; the jointed appendage attached at the apex of the leg. Thorax: the second or intermediate region of the insect body, bearing the true legs and wings, made up of three segments -- prothorax, mesothorax and metathorax.

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