Earwig - Morphology

Morphology

Most earwigs are flattened (to fit inside tight crevices, such as under bark) with an elongated body generally 7–50 millimetres (0.28–2.0 in) long, though some can grow longer, such as the Saint Helena earwig which reaches 80 mm (3.1 in) long. Earwigs are characterized by the cerci, or the pair of forceps-like pincers on their abdomen; male earwigs have curved pincers, while females have straight ones. 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 or more.

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 suborders Arixeniina and Hemimerina have no wings and are blind with filiform segmented cerci. 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. The epizoic species, sometimes considered as ectoparasites, are wingless.