Catchy tunes

from Wikipedia, the free encyclopedia
Catchy tunes
Common earwig (Forficula auricularia), female

Common earwig ( Forficula auricularia ), female

Systematics
Sub-stem : Trachea (Tracheata)
Superclass : Six-footed (Hexapoda)
Class : Insects (Insecta)
Subclass : Flying insects (Pterygota)
Superordinate : New winged wing (Neoptera)
Order : Catchy tunes
Scientific name
Dermaptera
De Geer , 1773

Earwigs (Dermaptera) are an order of the insects and belong to the flying insects (Pterygota).

Naming

From antiquity to the early modern period, the animals were powdered and administered as medicine against ear diseases and deafness . This is where the Latin name auricula ( deminutive of auris "ear") comes from . The terms earwig in English and perce-oreille in French are derived from this. Contrary to previous assumptions, earwigs are completely harmless to humans: Depending on the species, the pincers are used to hunt small insects, for wing development and for defense, not for pinching ears, as the name ear pincers might suggest.

In German-speaking animals under different regional variations of their names are known (eg. As Ohrenfitzler, earwigs, ears Klemmer, ears schliefer , Ohrlaus, Ohrawusler, ears brooder or Ohrkriecher).

General

Titanolabis colossea , the largest living earwigs from Australia with a length of over 6.5 cm

The body length of the animals is usually between 10 and 20 millimeters, some species can also become significantly larger, for example the giant earwig ( Titanolabis colossa ) with a body length of up to 50 millimeters. The now extinct St. Helena earwig ( Labidura herculeana ) was up to 80 millimeters long.

The front wings of the earwigs are roughly hardened and shortened (in Derma (to) ptera (Greek) derma means something like "leather"). They only cover the foremost part of the abdomen . The membranous hind wings are folded very complicated and compact under these wing wings. Only a few types of earwigs fly, some have completely regressed the flight muscles and the wings . The abdomen ends in a pair of abdominal threads, the cerci , which have been transformed into pincers , which are strongly curved in males and straight in females. This reorganization has also given them the colloquial name "Ohrenkneifer". The forceps are used for hunting, defense and as an aid in unfolding the hind wings as well as in mating. Most species have well-formed compound eyes . Point eyes ( Ocellen ) are always reduced.

Way of life

Earwigs prefer warm areas and habitats. They feed on parts of plants and litter , but some species are also predators and hunt smaller insects. Almost all species are active at night or at dawn and spend the day in self-made corridors, in hollow-core peaches, in the moist leaf sheaths of umbelliferous plants, under tree bark or stones and other hiding places.

The common earwig is omnivorous and is considered a beneficial insect , for example it eats aphids or caterpillars . But it is also a pest if it eats soft parts of plants, such as flowers. However, it cannot eat harder peel and skin: in the case of grapes or apples, it only uses the existing damaged areas and is not responsible for them. On apple trees you can find him often in the food aisles of the codling moth . Other species such as the sand earwig , Labidura riparia , are pure carnivores and can then help to reduce pests. As a rule, catchy tunes only produce one generation per year.

In addition to a very pronounced courtship behavior , brood care occurs in all investigated species . The eggs and larvae are protected in self-made hollows, but also in leaf grooves or under the bark, and are often cared for and cleaned, and sometimes even fed.

Taxonomy

The name Dermaptera was introduced by Carl de Geer , originally for a group that, in addition to earwigs, also includes grasshoppers , catchers and cockroaches . This is why the name Dermatoptera , introduced by Burmeister (1838), is occasionally used to express that one refers exclusively to the earwigs.

The 1800 known species are divided into three groups, which differ mainly in the way of life and the training of the eyes and wings.

Forficulina

The eyes of the Forficulina are very well developed, most species have well-developed wings. Most types of earwigs belong to this group, among them all species occurring in Central Europe:

Sand earwig ( Labidura riparia ) (male)

Arixeniina

In the Arixeniina the complex eyes are only small, wings are missing. A well-known species is the Phorent living on bats, Arixenia esau in Malaysia . The viviparous Arixeninae live exclusively on or near bats in Malaysia and the Philippines.

Hemimerina

In the hemimerina , both the complex eyes and the wings are completely reduced. All species live on the giant hamster rats ( Cricetomys ) in Africa , where they probably feed on skin fungi and scales. It has never been shown that the hemimerina would harm the giant hamster rats. Therefore, the Hemimerina are not to be described as parasites , but as mutualists or possibly symbionts .

Phylogeny

Phylogeny of the earwigs (Dermaptera) according to Popham 1985

The most preferred theory of earwig phylogeny was put forward in 1985 by EJ Popham on the basis of genital morphological studies. In his representation, the Arixeniina represent only one taxon within the Forficulina.

More recent hypotheses by Haas and Kukalova-Peck (1995 and 2001) sometimes deviate strongly from this phylogenetic hypothesis, although they are far better substantiated than Popham's hypotheses and supported by molecular work.

Fossil evidence

Earwigs have been known since the Jura . Adults are represented by four species of the genus Forficula from different tertiary amber deposits (especially the Baltic amber Eocene age). In amber, inclusions with larvae have also been found, which are assigned to the genera Forficula , Labidura and Pygidicrana .

Web links

Commons : catchy tunes  - collection of pictures, videos and audio files

Individual evidence

  1. ↑ Gundolf Keil : The fight against earwigs according to the instructions of late medieval and early modern German pharmacopoeias . In: Journal for German Philology. Volume 79, 1960, pp. 176-200.
  2. ↑ George O. Poinar, Jr .: Life in Amber. 350 pages, 147 pictures, 10 plates. Stanford University Press, Stanford (Cal.) 1992, ISBN 0-8047-2001-0 .
  3. ↑ Wolfgang Weitschat, Wilfried Wichard: Atlas of plants and animals in the Baltic amber. 256 pages, numerous illustrations. Pfeil-Verlag, Munich 1998, ISBN 3-931516-45-8 .