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DERMAPTERA
{earwigs}

The Order Dermaptera consists basically of "Earwigs". The number of species in the world is only about 1800. in 10 families. The number of species in the United States is about ??? species in ?? families. The number of species in Britain is 4 in 2 families. Earwigs are elongated insects with no wings or the front wings are hardened into leathery wing-cases (elytra).

These are odd looking insects with pincers on the end of their abdomens, use the pincers to capture and hold prey, for protecting themselves, and for helping to fold the hind wings. Contrary to myth, earwigs do not normally crawl into a person's ears.

The scientific name Dermaptera refers to the leathery fore wing (Greek origin: dermatos: skin, pteron: wing). This name was originally given by de Geer in 1773. de Geer used the name for all orthopteroids, so it was Kirby in 1815, who introduced the name Dermaptera, to be used in the modern sense.

Members of the Order Dermaptera are long, slender insects with a prognathous head. If a species is not wingless, then the thorax bears two pairs of wings, of which the first one is small and leathery and is called tegmina. The second pair of wings are large, membraneous, and are almost semi-circular. When at rest the wings are folded underneath the tegmina in a complicated manner. The abdomen of living Dermaptera is very movable, has as stated above, has a pair of unsegmented pinchers (called cerci, which are (not always forceps-like) at its posterior end. The body length ranges from approximately 1/8" to 3" in length including its antennae (4 to 80 mm including cerci).

For the most part, Dermaptera are colored brown or black and sometimes with a pattern which may be light brown or yellowish. Other colors, such as a metallic green is rare. Dermaptera are found throughout the world., except for the polar regions, as with many other insects. Dermaptera species have their greatest diversity in the tropics. FemaleDermaptera show maternal care, something not common in insects.

The natural history of Dermaptera is relatively unknown. Most of the studies done, have been in Europe. Some species which have been studied are the Forficula auricularia, the common earwig; Labidura riparia, the striped earwig and Anisolabis maritima, the seaside earwig.

Most species will eat most anything (i.e. they are omnivorous). However, Dermaptera predominantly feeds on plants (i.e. they are phytophagous) or prey on other animals (most insects, i.e. they are predacious). Some species of Dermaptera feed upon decaying plant and other material lying on damp earth. The Hemimerina sp. feed on scurf and fungi on the skin of giant rats which does not harm the rat. Skin gland secretions of bats and dead insects make up the food for the Arixenina sp. of Dermaptera.

Dermaptera's fossil record first appears about 208 MYA, in the Jurassic Epoch (Carpenter, 1992). There are about 70 specimens of fossil Dermaptera, according to the literature relied upon. Dermaptera fossils from the earliest periods, are remarkably similar to Dermaptera found today and recently. However, the fossil adult Dermaptera have segmented cerci (pinchers). .

Protelytroptera is most likely the stem group from which the Dermaptera arose (Carpenter, 1992; Hennig, 1969). The Protelytroptera insects were known from the Permian Epoch (290 MYA) in North America, Europe and Australia (Carpenter, 1992) and resemble modern Blattodea or Cockroaches.
Unfortunately, there appear not to be any fossils from the Triassic, when the morphological changes to Dermaptera from Protelytroptera happened.

Dermaptera are insects which search in close contact to the surface (thigmotactic). Earwigs like to crawl into humid cracks and crevices of all kinds. You can often find them under bricks, rocks, bark, and other things lying on the surface of the ground, but which have some moisture and decaying grass or other plant material under such items.: you can find them under bark, between leaves and under stones.

Undoubtedly at some times in history, Earwigs, looking for a moist dark place to hide, may have crawled into human's ears. The belief by some was that the Earwigs do this to penetrate the ear drum (tympanum) and the females would then lay eggs on the surface of the brain. This is not true and is undoubtedly gives rise to the name and reputation of these relatively innocuous insects.


Much of the information just supplied came from a source which you may want to go to for further information on the Order of Dermaptera. The organization is Tree of Life Web Project, and their website is: http://tolweb.org/tree?group=Dermaptera&contgroup=Neoptera


There is a good deal more information available on this Order on the Net, but this is probably more than most of our readers ever wanted to know about Earwigs. For more information, use your browser, as I did, looking for Dermaptera earwigs.