Bugs Order Hemiptera

Identification: FW usually thickened at base, membranous at tip. HW membranous, shorter than FW. Wings at rest held flat over body, tips of FW usually overlapping (some bugs are wingless, and a few have FW uniformly thickened). Mouth parts sucking. Beak generally rises from anterior part of head, and consists of 4 hairlike stylets in a segmented sheath. Palps lacking. Antennae of 5 or fewer principal segments, long and conspicuous or short and concealed. 2 ocelli or none. Tarsi with 3 or fewer segments. Metamorphosis simple.

Similar orders: (1) Homoptera (p. 128): FW uniform in texture, membranous or thickened; beak rises from hind part of head; antennae short and bristlelike or long and containing more than 5 segments. (2) Coleoptera (p. 146): FW uniformly thickened, nearly always meeting in a straight line down back; mouth parts chewing; antennae usually with 8 or more segments; tarsi often 4- or 5-segmented. (3) Orthoptera (p. 76): mouth parts chewing; FW uniformly thickened; HW with many veins; antennae many-segmented.

Immature stages: Similar to adult but wings small or absent. Habits: This is a large order and its members vary in habits. Most bugs are terrestrial, but many are aquatic and a few are external parasites of vertebrates. Many bugs are plant feeders, and many are predaceous on other insects.

Importance: A number of bugs are pests of cultivated plants; a few are bloodsucking and are irritating pests, and some of these are disease vectors. Some predaceous bugs are of value in keeping pest species under control.

Classification: Two suborders, Cryptocerata and Gymnocerata, differing in the character of the antennae. The principal characters used in separating families of Hemiptera are those of the beak, antennae, front wings, and legs. No. of species: World, 23,000; N. America, 4500.

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