Earwigs – Order Dermaptera

The name earwig comes from Old English eare “ear” and wicga “insect”. It is fancifully related to the notion that earwigs burrow into the brains of humans through the ear and therein lay their eggs. This belief, however, is false. Nevertheless, being exploratory and omnivorous, earwigs probably do crawl into the human ear; even if they are only looking for a humid crevice in which to hide, such behavior provides a memorable basis for the name.

Earwig is the common name given to the insect order Dermaptera characterized by membranous wings folded underneath short leathery forewings (hence the literal name of the order—”skin wings”). The abdomen extends well beyond the wings, and frequently, though not always, ends in a pair of forceps-like cerci. With about 1,800 recorded species in 10 families, the order is relatively small among Insecta. Earwigs are, however, quite common globally. There is no evidence that they transmit disease or otherwise harm humans or other animals, despite their nickname pincher bug.

Physiology
Most earwigs are elongate, flattened, and are dark brown. Lengths are mostly in the 10–14 mm range, with the St. Helena earwig reaching 80 mm. Cerci range from nonexistent to long arcs up to one-third as long as the rest of the body. As in other orthopteroid insects, mouthparts are adapted for chewing. When earwigs have wings (are not agnathous), the hindwings are folded in a complex fashion, so that they fit under the forewings. Earwigs rarely fly.

The abdomen of the earwig is flexible and muscular. It is capable of maneuvering as well as opening and closing of the forceps. The forceps are used for a variety of purposes. In some species, the forceps have also been observed in use for holding prey, and in copulation. The forceps tend to be more curved in males than in females.

Most earwigs found in Europe and North America are Forficula auricularia, the European earwig, which is distributed throughout the cooler parts of the northern hemisphere. They feed on other insects, plants, ripe fruit, and garbage. Plants they feed on typically include clover, dahlias, zinnias, butterfly bush, hollyhock, lettuce, strawberry, sunflowers, celery, peaches, plums, grapes, potatoes, roses, seedling beans and beets, and tender grass shoots and roots; they have also been known to eat corn silk, damaging the corn. Typically they are a nuisance because of their diet, but normally do not present serious hazards to crops. Some tropical species are brightly colored. Occasionally earwigs are confused with cockroaches because of their cerci and their long antennae. Earwigs are most active at night and can be seen patrolling household walls and ceilings. Interaction with earwigs at this time results in a defensive free fall to the ground below, and the subsequent scramble to a nearby cleft or crevice.

Earwigs are drawn to damp conditions. During the summer they can be found around sinks and in bathrooms. Earwigs tend to gather in shady cracks or openings or anywhere they can remain concealed in daylight hours. Picnic tables, compost and waste bins, patios, lawn furniture, window frames or anything with minute spaces can potentially harbour these unwanted residents. Upon gaining entry to the basement and living areas of the home, earwigs can easily find cover in undisturbed magazine and newspaper piles, furniture/wickerwork, base boards, carpeted stairways, pet food dishes, and even inside DVD cases and keyboards. Earwigs are inclined to take risks and are exploratory creatures but are overly unaware of the consequences and are often found trapped in poison baited cups or buckets of soapy water.

Pest control
While earwigs can be considered in some ways a beneficial part of the garden, they can become a nuisance because of their diet. Since they prefer cool, moist places, a rolled up damp newspaper placed where earwig activity is suspected can be effective in collecting them. The newspaper can then either be discarded or shaken out. Placing diatomaceous earth in key spots around the home (bathroom, baseboards, window frames) can be a long-term repellent.

Another method of removing earwigs is by utilizing their attraction to vegetable oil. Putting vegetable oil in a pie tin and burying it up to the rim of the tin is an effective way of capturing them. Another effective method of earwig control is to take steps to control the population before they hatch by removing rotting underbrush and spraying with commercially available insecticidal nematodes, which invade the earwigs in their nymphal stage and infect them with a lethal bacterium.

Some persons report being able to reduce earwig populations around the house by trapping. Place burlap bags, boards, newspapers or other cover material on mulch, shrubbery and similar habitats. Collect individuals that congregate under the cover and discard. As a last resort insecticides can be sprayed around the house to stop or limit earwigs from getting indoors. Treat a three to six foot band around the house adjacent to the foundation (perimeter treatment). Apply a home garden or turfgrass insecticide labeled for this purpose as needed and according to label directions. Applications in late afternoon are preferred. Use sufficient spray water (or post-treatment irrigation) to move the insecticide through mulch materials to the hiding places underneath. Insecticides available for this use by homeowners in Iowa include carbaryl (Sevin), cyfluthrin, permethrin and several more.
–From Wikipedia, the free encyclopedia