Earwig

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iEarwigs

Common earwig, Forficula auricularia

Scientific classification

Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Hexapoda
Class:	Insecta
Order:	Dermaptera De Geer, 1773

Families

Suborder Archidermaptera

extinct

Suborder Forficulina

Pygidicranidae

Diplatyidae

Anisolabididae

Labiduridae

Apachyidae

Spongiphoridae

Chelisochidae

Forficulidae

Suborder Hemimerina

Hemimeridae

Suborder Arixenina

Arixeniidae

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.

1 Etymology
2 Physiology
3 Pest control
4 References
5 External links

[edit] Etymology

Earwig from Australia compared to a CF card - 63 mm

The name "earwig" is generally said to originate from an old European belief that earwigs crawl into people's ears and lay eggs in the brain. This etymology is given by the Oxford English Dictionary, which states unequivocally that the name is derived from Old English éare, "ear", and wicga, "insect", "from the notion that it penetrates into the head through the ear." Earwigs do tend to prefer being in hidden places, and this etymology parallels the unambiguous French name perce-oreille ("ear piercer"). Another hypothesis is that the word comes from the Late Latin auricula, owing to the ancient use of pulverized earwigs as medicine to treat diseases of the ear. A third explanation is that it is an alteration of "ear-wing", after the shape of the hind wings when unfolded.

[edit] 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.

Female (cerci not hooked)

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, 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 the points on the end, the 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 also 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. Earwigs are inclined to take risks and are exploratory creatures but are overly unaware of the consequences and will often find themselves trapped in poison baited cups or buckets of soapy water.

An earwig from the Western Ghats

[edit] 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 using 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. The oil can then be reused in the tin after disposing of the earwigs.