Species Forficula auricularia - European Earwig

Forficula auricularia Linnaeus 1758

body 12-15 mm; forceps: ♂ 4-8 mm ♀ ~3 mm

Male forceps (distinctive among North American earwigs) vary from about half as long to longer than the abdomen, broadened basally, with crenulate teeth basally and on beginning of curvature of inner margin. Antennae have 12-15 segments. Adult wings completely developed.

♂ ♀

wing fully opened:

Essentially identical to F. dentata, but note introduced range.

Cosmopolitan, native to western Palaearctic; widely though spottily distributed across NA*; introduced from Europe around 1910(1)

*Forficula auricularia is no longer recognised in BC, WA, ID, OR, CA, and NV.

The female lays a clutch of eggs, which she tends and grooms in order to keep it clean and safe.

The immature earwigs are basically like miniature, undeveloped versions of the parents, with wings developing gradually on the outside of the body with each molt, the number of segments in the antennae also increasing with each molt, and the forceps developing from thin rods into the characteristic shapes of the adults. The female continues to look after them after hatching (at least in the early stages).

Fecal pellets are often found in the nests; these serve as a emergency food source under starvation conditions.(2)