page_title: Earwig
section_title: Morphology
hierarchical_section_title: Earwig / Morphology
caption_attribution_description: English: Illustration of Dermaptera morphology from Fauna of British India. 1910. Dermaptera. Malcolm Burr (1878-1954) but book in public domain as work of Indian government done prior to Indian independence in 1947.
context_page_description: Earwigs make up the insect order Dermaptera. With about 2,000 species in 12 families, they are one of the smaller insect orders. Earwigs have characteristic cerci, a pair of forceps-like pincers on their abdomen, and membranous wings folded underneath short, rarely used forewings, hence the scientific order name, "skin wings." Some groups are tiny parasites on mammals and lack the typical pincers. Earwigs are found on all continents except Antarctica.
  Earwigs are mostly nocturnal and often hide in small, moist crevices during the day, and are active at night, feeding on a wide variety of insects and plants. Damage to foliage, flowers, and various crops is commonly blamed on earwigs, especially the common earwig Forficula auricularia.
  Earwigs have five molts in the year before they become adults. Many earwig species display maternal care, which is uncommon among insects. Female earwigs may care for their eggs, and even after they have hatched as nymphs will continue to watch over offspring until their second molt. As the nymphs molt, sexual dimorphism such as differences in pincer shapes begins to show.
context_section_description: Most earwigs are flattened (which allows them to fit inside tight crevices, such as under bark) with an elongated body generally 7–50 millimetres (0.28–1.97 in) long. The largest extant species is the Australian giant earwig (Titanolabis colossea) which is approximately 50 mm (2.0 in) long, while the possibly extinct Saint Helena earwig (Labidura herculeana) reached 78 mm (3.1 in). Earwigs are characterized by the cerci, or the pair of forceps-like pincers on their abdomen; male earwigs generally have more curved pincers than females. These pincers are used to capture prey, defend themselves and fold their wings under the short tegmina. The antennae are thread-like with at least 10 segments.
  The forewings are short oblong leathery plates used to cover the hindwings like the elytra of a beetle, rather than to fly. Most species have short and leather-like forewings with very thin hindwings, though species in the former suborders Arixeniina and Hemimerina (epizoic species, sometimes considered as ectoparasites) are wingless and blind with filiform segmented cerci (today these are both included merely as families in the suborder Neodermaptera). The hindwing is a very thin membrane that expands like a fan, radiating from one point folded under the forewing. Even though most earwigs have wings and are capable of flight, they are rarely seen in flight. These wings are unique in venation and in the pattern of folding that requires the use of the cerci.
caption: Male earwig, external morphology. Click on image for a larger view
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