Common shrub insect
| Common shrub insect | ||||||||||||
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Common shrub hedge ( Pholidoptera griseoaptera ), ♂ |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Pholidoptera griseoaptera | ||||||||||||
| ( De Geer , 1773) |
The common shrub insect ( Pholidoptera griseoaptera ) is a long- probe insect from the superfamily of the leaf locust (Tettigonioidea). The flightless animals inhabit a number of different habitats, but avoid sandy habitats.
features
The animals reach a body length of 13 to 20 millimeters (males) or 15 to 20 millimeters (females) and are thus much smaller than the similar alpine shrub insect ( Pholidoptera aptera ). The scythe-shaped, upwardly curved and evenly tapering laying tube ( ovipositor ) of the females is another 8 to 10 millimeters long. The horrors have a gray to dark brown, rarely red-brown or yellow-brown body color, their belly is markedly yellow. The sides of the pronotum have a very fine white border, this distinguishes the species from the Alpine shrub insect, in which the rear edge of the pronotum is broadly yellowish-white in color. Males and females are unable to fly because the wings have largely receded. In the females, the forewings measure an average of only 1.22 millimeters (extreme values 0.9-1.6 millimeters) and just protrude below the pronotum. The hind wings are also only small, 1.05 millimeter long stubs (mean value from measurements in ten females). In the males, the hind wings are regressed in the same way (mean: 1.07 millimeters according to measurements in 40 males), while the forewings are noticeably larger with an average of 4.36 millimeters (extreme values: 3.8-5.0 millimeters) than with the females, because they still have the structures that are used for sound production (picture). The front wings of the males are rounded, arched upwards, brown, outside light brown to ocher in color. According to their functions, the left and right fore wings are designed differently in the males. On the left wing the shrill loaders and the shrill ledge measure an average of 3.41 and 2.56 millimeters, respectively, while on the right wing the shrill loaders and the shrill ledge are only 2.68 and only 1.95 millimeters long. The left, active shrill bar has an average of 103.58 shrill teeth, the right only 83.74. In contrast, the mirror on the right wing is excellently designed, while it is no longer applied on the left wing (picture). The long cerci of the males are provided with a pointed tooth after the first quarter.
Occurrence
The common shrub insect is widespread from northern Spain and Ireland to the Crimea peninsula and the Caucasus in the east. The species is particularly common in Central Europe, but it is rarer to the north and also in the Mediterranean region. It occurs from the lowlands to altitudes of around 2100 meters, most often below 1000 meters, over 1400 meters only in some regions, such as parts of Switzerland. The animals inhabit different habitats with medium to high vegetation, especially forest edges or clearings as well as hedges and dense vegetation along streams, also high-growing meadows and ruderal areas, parks and gardens. The species often occurs together with the Alpine shrub insect. The common shrub insect is one of the first to colonize clearcuts, it avoids sandy soils and is accordingly absent in sandy areas, such as on inland dunes , even when otherwise suitable vegetation structures prevail.
Way of life
The adults mainly feed on small insects like aphids or caterpillars, but also eat plants like dandelions, bed herbs and nettles. The larvae feed initially exclusively from plant foods. The animals need very little heat and are active at temperatures above 7 ° C. Adult animals have a hidden way of life and stay in tall grass or between herbaceous plants, and also climb trees, where they are found in the crowns of gray and black alders . In the morning they sunbathe and finally hike into the dense vegetation during the day. On cool or humid days they stay on the sunny side of their habitat, while it is dry and hot on the shady side.
singing
The males sing from the afternoon until late at night. Since the species needs little warmth, the song can also be heard on cool and damp nights, even after night frosts. It consists of three syllables, the amplitude of which increases. The frequency of these "zizizi" sounds is around 40 Hz . The intervals between the short verses range from 0.5 to three seconds. At higher temperatures, the three individual syllables are combined into a sharp “zrit”. If the male perceives a rival, the gaps between the “zrit” verses are shortened and irregular rows are played, which follow one another closely and become louder. The singing can be heard up to 10 meters away.
development
The females lay their eggs in the ground as well as in dead branches, dead wood and the like. The eggs require increased moisture. The females take this into account and lay the eggs in warm habitats deeper in the shady forest. In the course of their embryonic development, the eggs mostly end up in the leafy layer on the ground. A total of about 200 of the 4.5 mm long and 1.2 mm wide eggs are laid. The larvae need two full years to develop and go through seven larval stages. The eggs laid in autumn hibernate and develop over the course of the following summer, depending on the prevailing temperatures. Soil substrate directly exposed to sunlight enables faster development due to the warmer temperature. The larvae hatch only after a second hibernation between April and June of the third year. Often they sit freely on leaves or in the grass. The first adults appear from June and can be observed until the end of November at the latest.
Danger
The common shrub insect is widespread due to its wide range of habitats, occurs frequently in Central Europe and is therefore not endangered.
supporting documents
Individual evidence
- ↑ a b Anna Alfonsa Stark: Investigations on the sound organ of some crickets and grasshopper species, at the same time a contribution to the right-left problem. Zoological Yearbooks, Department of Anatomy and Ontogeny of Animals 77, pp. 9–50, 1958.
- ↑ a b c Heiko Bellmann : The cosmos of locust leader. Determine the species of Central Europe with certainty . Franckh-Kosmos, Stuttgart 2006, ISBN 3-440-10447-8 , pp. 138 .
- ↑ a b c d e Bertrand & Hannes Baur, Christian & Daniel Roesti: The locusts of Switzerland . Haupt Verlag, Bern 2006, ISBN 3-258-07053-9 , p. 122 f .
- ↑ a b c d e f g Peter Detzel: The locusts of Baden-Württemberg . Eugen Ulmer, Stuttgart 1998, ISBN 3-8001-3507-8 , pp. 278 ff .
literature
- Anna Alfonsa Stark: Investigations on the sound organ of some crickets and grasshopper species, at the same time a contribution to the right-left problem. Zoological Yearbooks, Department of Anatomy and Ontogeny of Animals 77, pp. 9–50, 1958.
- Bertrand & Hannes Baur, Christian & Daniel Roesti: The locusts of Switzerland. Haupt Verlag, Bern 2006, ISBN 3-258-07053-9 .
- Heiko Bellmann : The cosmos of locust leaders, defining the types of Central Europe with certainty. Franckh-Kosmos Verlags-GmbH & Co KG, Stuttgart 2006, ISBN 3-440-10447-8 .
- Peter Detzel: The locusts of Baden-Württemberg. Verlag Eugen Ulmer GmbH & Co, Stuttgart 1998, ISBN 3-8001-3507-8 .
