Forficula auricularia is a species complex comprising the common earwig. It is also known as the European earwig. It is an omnivorous insect belonging to the family Forficulidae. The name earwig comes from the appearance of the hindwings, which are unique in their resemblance to human ears when unfolded. The species name of the common earwig, auricularia, is a specific reference to this feature. The European earwig survives in a variety of environments. It is also a common household insect in North America. They are often considered a household pest because of their tendency to invade crevices in homes and consume pantry foods, though they may also act as beneficial species depending on the circumstances.

Forficula auricularia is reddish-brown in color with a flattened elongated body and slender beaded antennae. Earwigs possess pairs of pincers or forceps at the tip of the flexible abdomen. Both sexes have these pincers. In males, they are large and curved, whereas in females, they are straight. Nymphs are similar to adults in appearance, though their wings are either absent or small.

Forficula auricularia have elongated flattened brownish-colored bodies, with a shield-shaped pronotum, two pairs of wings, and a pair of forceps-like cerci. They are about 12–15 mm (0.47–0.59 in) long. The second tarsal segment, which is located on the leg, is lobed, extending distally below the third tarsal segment. The antenna consists of 11–14 segments, and the mouth parts are of the chewing type.

An anatomical diagram of the common earwig can be found to the right. Section A represents the head, B represents the thorax, and C represents the abdomen. The numbers correspond to different body parts. 1 is pointing to the pronotum (a plate-like structure that covers the thorax), and 2 is pointing to the elytra (tough outer wings used to protect the more delicate hind wings). 3 is pointing to the delicate hind wings peeking out, and 4 is pointing to the abdomen. 5 is pointing to the cerci (paired appendages on the abdomen of many insects).

A detailed analysis of mitochondial DNA from specimens across Europe has established that Forficula auriculata is a complex of several morphologically indistinguishable species. There are at least four species in the Forficula auricularia complex: Forficula auricularia, Forficula dentata, Forficula mediterranea, and Forficula aeolica.

The name Forficula auriculata applies to those found in Scandinavia and Central Europe, whereas Forficula dentata is the usual species found in the British Isles and Western Europe. There are several other members of the complex distinguished based on mitochondrial haplotypes.

In North America, European earwigs were found to comprise two sibling species, which are reproductively isolated. Populations in cold continental climates mostly have one clutch per year, forming Forficula auriculata whereas those in warmer climates have two clutches per year, forming Forficula dentata.

Originating in Europe, western Asia and possibly North Africa, Forficula auricularia was introduced to North America in the early twentieth century and has since spread throughout much of the continent. It was accidentally introduced into New Zealand by Early European settlers. European earwigs are most commonly found in temperate climates, since they were originally discovered in the Palearctic region, and are most active when the daily temperature has minimal fluctuation.