Other Common Names
Pincher Bugs; Tesourinha ('Little Scissors' In Portuguese).
Synonyms and other taxonomic changes
initially Dermaptera was defined to include roaches, mantids, grasshoppers and crickets, etc.
NB: Dermoptera is a mammals order (Flying Lemurs).
Explanation of Names
Dermaptera = 'skin wings' (refers to the leathery texture of the forewings)
Earwig is from Old English eár-wicga 'ear-crawler' (folklore claims earwigs creep into human ears)
Numbers
3 suborders. Forficulina is the largest one.
27 spp. in 12 genera of 6 families in our area
(1)(2)(3), ~1800 spp. in >200 genera of 11 families worldwide
(4)
Overview of our faunaincludes commonly intercepted genera • * –taxa not yet in the guide • classification follows(4)
Order Dermaptera
Suborder Neodermaptera (the only extant suborder)
Size
6-35 mm (not counting cerci)
Identification
Earwigs have slender flattened body, bead-like antennae, and are easily recognized by the pair of large pincers (
cerci) at the tip of the abdomen. Adult males have 10 abdominal
tergites; females, 8. Some are wingless, but in most the fore wings are represented by short leathery covers called
tegmina, under which the hind wings (if present) fold in a unique fan-like fashion leaving a
chitinized triangular part exposed.
The pincers' shape is highly species-specific in males (asymmetrical in some groups) but quite uniform in females throughout the order.
Key to genera occurring north of Mexico: Engel 2003
(5)
Quick visual guide
Anisolabididae (=Carcinophoridae)
Forficulidae
Labiduridae
Labiidae
Chelisochidae
Pygidicranidae
Range
Mostly in warm climates; very few range far north.
Habitat
Earwigs are sensitive to heat and dryness, so they usually hide in cool, dark places during the day and come out at night.
Some species hide mostly under leaves, rocks and other debris, while others hide under the bark of trees. An important habitat in the deserts of the southwest US is inside rotting cactus- one of the few places with constant moisture even in the driest parts of the year.
Winged species are often attracted to light at night
Season
Year-round, but often inactive/hiding in cold or dry weather.
Food
Plants, organic matter, other insects (some are almost exclusively carnivorous, and many are important in controlling soil pests).
Life Cycle
Simple metamorphosis with visible changes including increasing number of antennal segments and progressive wing development until sexual maturity. The mother cares for the eggs and nymphs.
Remarks
Earwigs were thought to crawl into people's ears at night to nest or lay eggs -- an obvious myth, possibly rooted in rare cases of an earwig accidentally wandering into the ear of someone sleeping in a damp place. Earwigs are harmless to people, though they may emit a foul-smelling liquid when disturbed or use their pincers in defense.
Some species often hide in cargo and are easily spread by commerce. Most of our species are non-native, and new ones show up regularly in ports, though few get established.
See Also
Rove beetles (Staphylinidae) can look very similar, especially in the small size and placement of their hardened forewings. Although they may have small cerci at the tips of their abdomens, they have nothing like the large unsegmented and movable pinchers of the earwigs:
