Arctic emerald dragonfly
| Arctic emerald dragonfly | ||||||||||||
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Somatochlora arctica , male |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Somatochlora arctica | ||||||||||||
| ( Zetterstedt , 1840) |
The arctic emerald dragonfly ( Somatochlora arctica ) is a species of dragonfly from the family of falcon dragonflies (Corduliidae), which belong to the large dragonflies (Anisoptera). The species is considered endangered in Germany, in Lower Saxony it is classified as critically endangered.
features
These dragonflies reach a wingspan of six to seven centimeters. Characteristic is a pair of yellow spots on the sides of the third abdominal segment. The distinction from other green-blackish somatochlora species, such as the Alpine emerald dragonfly ( Somatochlora alpestris ) or the shiny emerald dragonfly ( Somatochlora metallica ), is best carried out on the basis of the curved upper abdominal appendages in the males or the shape of the laying flap (females) .
Occurrence and habitat
The species, which is widespread in Eurosiberia, lives in the smallest of water points in peat moss - swinging grass within bogs. In southern Germany it occurs almost only in the low mountain ranges and in the Alpine region, in the north also in the raised bogs of the lowlands. Overall, Somatochlora arctica is very rare. For example, only five places are known in the Netherlands where it occurs.
Way of life, reproduction and development
The males behave similarly to the Alpine emerald dragonfly and patrol over the swinging lawn in search of females. They like to sit on plants close to the ground.
Mating lasts around half an hour and begins in the air. Then the pairing wheel settles on a tree or in the bushes. The females lay their eggs in flight. The larvae partially hatch before winter or overwinter in the egg before hatching in spring. They live in tiny water holes between peat moss or sedge rhizomes and need two to three years for their development. During this time, the larvae also tolerate periods of drought lasting several weeks. If necessary, they can move into deeper peat moss layers with the sinking water. With permanent dehydration, the larvae migrate to more suitable habitats a few meters away. They can also survive a complete freeze of up to three weeks.
Individual evidence
- ^ A b Jaap Bouwman, Dick Groenendijk: New records of Somatochlora arctica in northwestern Lower Saxony (Odonata: Corduliidae) . Libellula 26 (1/2), 2007: 35-40
- ↑ Klaus Sternberg: Somatochlora arctica (Zetterstedt, 1840) - Arctic emerald dragonfly. S. 261 in: Sternberg / Buchwald (Ed.): Die Libellen Baden-Württemberg. Volume 2: Dragonflies (Anisoptera). Ulmer, Stuttgart 2000, ISBN 3-8001-3514-0
literature
- Gerhard Jurzitza: The Kosmos dragonfly guide . Franckh-Kosmos Verlags GmbH & Co., Stuttgart 2000, ISBN 3-440-08402-7
- Klaus Sternberg (1995): Influence of oviposition date and temperature upon embryonic development in Somatochlora alpestris and S. arctica (Odonata: Corduliidae). - J. Zool. Lond., 235: 163-174.
- Klaus Sternberg (2000): Somatochlora arctica (Zetterstedt, 1840). Pp. 251-264. in: Sternberg / Buchwald (ed.): Die Libellen Baden-Württemberg. Volume 2: Dragonflies (Anisoptera). Ulmer, Stuttgart, ISBN 3-8001-3514-0
