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Dermaptera
Exopterygota

Dermaptera is the order which compromises of Earwigs.

Morphology[]

Often regaurded as a pest in gardens and farms they generally are reddish-brown to black in color and their legs are most often pale yellow. The shape of adult earwigs is elongated, and they are slightly flattened. When fully grown, they are about 16 mm long. Earwigs have long antennae, but their notable characteristic is the forceps protruding from their hind ends. Males tend to have larger and more inward-curving forceps than females. Earwigs have chewing mouthparts. If disturbed, earwigs can emit a noticeably foul odor. The name “earwig” comes from an old European superstition that earwigs enter peoples’ ears and bore into the brain.

Metamorphosis[]

In the spring or summer, earwig eggs are laid into the ground in moderate-sized batches of 25-50. Females are maternal and are protective of the eggs and the nymphs, and they will stand guard near the burrow where the eggs were laid. Eggs laid in the spring hatch in a little over two months, while eggs laid in the summer hatch in about three weeks. Nymphs go through four stages and two development phases as they grow into adults, becoming more independent in foraging for food. Adulthood is reached late summer, and this is when mating occurs. Most earwig species overwinter as adults.

Economical Importance[]

Earwigs are beneficial because they feed on soft-bodied pests such as aphids and on insect eggs. However, they can be of economic importance because they also feed on soft plant tissues such as leaves and fruits. This behavior can be unfortunate for the home gardener. Some species are scavangers or may be potentially saprophytic by metabolsim. They can help speed up the process of decomposition.

Urban Impact[]

Earwigs may pose a problem when large numbers try to enter homes for shades, shelter, and moisture. Earwigs may feed and survive on pantry food items although they are not known to lay eggs and reproduce indoors. Despite the menacing pincer-like protrusion in the hind end of the insect, earwigs do not directly harm humans or pets. The pincer-like structure on an earwig’s hind end is termed cerci (pronounced “sir-see”) and is used as a defensive mechanism and to capture preys.

Ecology[]

Control of earwig indoors hinges mainly on excluding earwigs from entering homes. Earwigs enter human dwelling through cracks in foundations and gaps around doors or windows. Caulk the cracks around doors, windows, foundations, and outdoor water faucets. Weather strips may also be used to seal gaps around doors and windows to prevent earwig entry. Earwigs prefer damp and shady shelter provided by pot plants, mulches, leaf debris and firewood piles. Removing such hiding areas from around the foundation and creating a clean, dry border around the house foundation should discourage further earwig invasion indoors.

Prevention[]

Earwigs found in homes are best controlled by vacuuming or killed by hand. Because earwigs are not known to lay eggs indoors, a continual problem with earwigs signals continuous invasion from outdoor sources. In the case of bad infestation indoors, consider doing perimeter spraying on the house foundation using insecticides labeled for this type of application. Always use precaution and follow the label carefully before using any insecticide. Insecticides have a certain amount of toxicity to mammals; children and pets are especially at risk.

Geographical range[]

Earwigs are abundant and can be found throughout the Americas and Eurasia. The common earwig was introduced into North America in 1907 from Europe, but tends to be more common in the southern and southwestern parts of the United States. The only native species of earwig found in the north of the United States is the spine-tailed earwig (Doru aculeatum), found as far north as Canada, where it hides in the leaf axils of emerging plants in southern Ontario wetlands. However, other families can be found in North America

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