Common water strider
| Common water strider | ||||||||||||
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Gerris cf. lacustris when mating |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Gerris lacustris | ||||||||||||
| ( Linnaeus , 1758) |
The common water strider ( Gerris lacustris ) is a bug from the family of water striders (Gerridae). The bed bugs, which slide quickly over water surfaces, are widespread and common in Europe.
features
The bugs reach body lengths between 8 and 10 millimeters. The thighs ( femur ) of the front legs, which are attached to the first breast segment, are yellowish and have two black longitudinal stripes. They are mainly used to capture the prey. As with all species of the genus, the middle and rear pair of legs are greatly elongated compared to the front, which is also angled. These two pairs of legs are spread out from the body in a cross shape. The middle legs are moved simultaneously, the rear legs are used for control. The body and legs are covered with an extremely thick felt made of water-repellent hair. In contrast to other species of the genus, the pronotum has a continuous yellowish lateral stripe and the median longitudinal keel is very clear in the rear section. The wings of the individuals are very different. There are all gradations from long-winged and airworthy to wingless and flightless forms. Long-winged animals occur mainly in the autumn generation, with individuals of the summer generation the wings are greatly shortened or completely reduced. The species is difficult to distinguish from other members of the genus Gerris .
Occurrence
The animals are found all over Europe and North Africa, east to Siberia and China . They are widespread and common in Central Europe and occur in the Alps up to an altitude of around 1,500 meters. You can find them on almost all still water types of medium to small size. The trophy and the vegetation of the water body are irrelevant. Slowly flowing waters, those with low pH and slightly saline waters are also populated.
Way of life
The common water strider can appear on bodies of water together with all other species of the genus. A dense, air-containing hair felt on the underside of the body prevents wetting with water and enables movement on the water with the help of surface tension . The animals move jerkily, but can also make long jumps. They feed exclusively predatory on living or dead insects that have fallen into the water, which are grasped with the short front legs and then sucked out with the proboscis. Two generations are trained each year. The adults , which are fully grown from mid-July, insert a diapause and often overwinter far away from their living areas on land in the litter, under bark or stones. Mating does not take place until the spring of next year. The eggs are spread over several months individually or in rows just below the surface of the water with a gelatinous secretion attached to plants and the like.
literature
- Wolfgang Engelhardt: What lives in pools, brooks and ponds? - Kosmos Naturführer, 12th edition, Stuttgart 1986, ISBN 3-440-05444-6 .
- Ekkehard Wachmann , Albert Melber, Jürgen Deckert: Bugs Volume 1: Dipsocoromorpha, Nepomorpha, Gerromorpha, Leptopodomorpha, Cimicomorpha (Part 1) with Tingidae, Anthocoridae, Cimicidae and Reduviidae. - Goecke & Evers, Keltern 2006, ISBN 3-931-37449-1 .
- E. Wagner: Heteroptera Hemiptera. - In: Brohmer, P., P. Ehrmann, G. Ulmer (Hrsg.): Die Tierwelt Mitteleuropas. IV, 3 (Xa). - Leipzig 1959, 173 pp.
- E. Security guard: watch bugs - get to know. J. Neumann - Neudamm, Melsungen 1989, ISBN 3-7888-0554-4 .
