Common name(s): Earwigs
Description: Small to medium in size, earwigs are elongate and rather dorsoventrally flattened. They have prognathous mouthparts. Filiform antennae and legs are short. Compound eyes can be large, small or absent and ocelli are absent. If there are wings present, the forewings are small, leathery, unveined tegmina and the hindwings are large, membranous and semi-circular. The abdomen is telescoped. Immature nymph stages resemble the adults. The most recognizable feature of Dermaptera is the cerci, which are modified as forceps.
Fun facts: The Dermaptera order consists of around 1800 species in ten families worldwide. Copulation takes place end-to-end, and the male spermatophore can be retained by the female for use for several months. Oviparous species lay eggs in debris or litter and females guard the eggs. The female may then assist the nymphs to hatch and care for them until the second or third instar, at which time she may cannibalize her offspring.
There are two parasitic groupings (Gullan calls them 'tribes', but I am sure that is not the scientific wording), Arixeniina and Hemimerina, which reproduce using pseudoplacental vivipary.
Earwigs are cursorial and nocturnal with most species rarely flying. Most feed on dead and decaying vegetation and animal matter. There is some predation and damage to live plants. Arixeniina are commensal or ectoparasitic to bats in SE Asia. Hemimerina are semiparasitic on South African rodents. These parasitic earwigs are blind, apterous and have rod-like forceps. Free-living earwigs use their forceps to manipulate prey, for defence and fighting, and sometimes during reproduction to grasp the partner.
The common name of Dermaptera derives from a supposed predilection for entering ears of sleeping victims, but this cannot be substantiated. What can be substantiated is that they like to bite, as in the case of our very own Wertperch, who has been bitten twice by earwigs.
Dermaptera may be closely related to the Plecoptera and the Grylloblattodea, but the relationships within the Orthopteroid-Plecopteroid assemblage are unresolved.
sourced, in part, by The Insects: An outline of entomology, second ed. Gullan, P.J. and P.S. Cranston. Blackwell Science, Great Britain, 2000.