Tetragnatha obtusa
| Tetragnatha obtusa | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Tetragnatha obtusa |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Tetragnatha obtusa | ||||||||||||
| CL Koch , 1837 |
Tetragnatha obtusa is a spider from the family of the Strecker spider (Tetragnathidae). The species inhabits the crowns of shrubs and trees in large parts of the Palearctic . It is unmistakable in Central Europe because of its almost triangular rear body when viewed from the side.
description
The species is one of the smaller representatives of the genus in Central Europe; Males have a body length of 4.0 to 5.5 mm, females reach 4.5 - 6.5 mm. The front body ( prosoma ) is dark brown, in the area of the eyes and on the outer edge black-brown.
The rear part of the body ( opisthosoma ) is rounded to a point approximately in the middle and is therefore almost triangular when viewed from the side. On a whitish to greenish background it bears an irregular, brownish markings. The legs are indistinctly brown and ringed with black.
distribution and habitat
The species colonizes large parts of the Palearctic from the Canary Islands and Ireland to Kamchatka and China. The distribution area includes the arctic to subtropical zones. It occurs all over Europe.
Tetragnatha obtusa lives in deciduous and mixed forests and orchards that are not too moist . There it populates the canopy of bushes and trees.
Way of life
The species builds small wheel nets with an open hub on mostly dry branches . Like all species of the genus, Tetragnatha obtusa sits tightly pressed against the base when at rest, with the two pairs of forelegs stretched forward and the last pair of legs stretched backwards; the third pair of legs encircles the mat. Sitting on the underside of dry twigs, it imitates buds and is then excellently camouflaged. Sexually mature animals occur from June to August.
Danger
The species is widespread, but is found relatively rarely due to its habitat. In Germany it is classified as "safe" in the Red List .
Individual evidence
- ^ Map of the worldwide distribution of Tetragnatha obtusa from the British Arachnological Society
- ↑ Hänggi, Ambros; Stöckli, Edi; Nentwig, Wolfgang, 1995. Habitat of Central European Spiders. Miscellanea Faunistica Helvetiae - Center suisse de cartographie de la faune, Neuchatel. ISBN 2884140085
literature
- Ralph Platen, Bodo von Broen, Andreas Herrmann, Ulrich M. Ratschker & Peter Sacher: Total species list and red list of spiders, harvestmen and pseudoscorpions of the state of Brandenburg (Arachnida: Araneae, Opiliones, Pseudoscorpiones) with information on frequency and ecology. In: Nature conservation and landscape maintenance in Brandenburg. 8, issue 2 (supplement); 1999.
