Sunday, November 1, 2009


I think I'm starting to get lazy - when I realize I happen to have a picture of an insect which I have already identified and haven't yet done an entry about, I just pick that one to write about instead of getting out the scope and keying one of the ones I have on my pinning board. For this entry, I have chosen Forficula auricularia, or the European Earwig. Earwigs are very interesting insects, which most everyone has come across at one time or another, and in the US that type is almost always the European Earwig. Earwigs make up the order Dermaptera, and consist of slender, elongate, somwhat flattened insects that have forceps-like cerci (apical extensions from the abdomen). Adults may be winged or wingless, most have short, leathery, veinless wings that do not reach very far down the abdomen. They are hemimetabolous, meaning the immature earwigs look like miniature adults, though they have fewer antennal segments. They also have male abdomen characteristics (10 segments) and female cerci characteristics (straight forceps, not curved). The forceps are the easiest way to determine gender in mature earwigs.

Dermaptera; Forficulidae; Forficula auricularia
Common Name: European Earwig

Earwigs are generaly nocturnal and hide during the day in cracks, crevices, under bark, in flowers, in debris, etc. They mostly feed on dead and decaying vegetable matter, but some feed on living plants and a few are predaceous - both of the earwigs pictured above are male, based on the forceps, and the lower male is feasting on a small insect. Earwigs, like the Orthopterans and Mantids, are capable of emitting a foul-smelling fluid, which some are able to squirt for a distance of 1 cm. Earwigs do not bite, but are capable of pinching with their forceps when handled; it does not often break the skin. Unlike their name, they do not enter people's ears. Earwigs overwinter as adults, and the females exhibit maternal behavior - they guard their eggs until they hatch, and even then they look after the nymphs until they are ready to take care of themselves.

The family Forficulidae includes European and Spine-tailed Earwigs. The European earwig is the most common - it is a brownish-black insect 15-20 mm long and is distributed across North America. It can cause significant damage to crops and ornamental plants.

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