Food spider
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Spider ( Scytodes thoracica ) |
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| Scytodes thoracica | ||||||||||||
| ( Latreille , 1802) |
The food spider ( Scytodes thoracica ) is a species of spider from the family of food spiders . It is the only species of this family native to Central Europe . The spider inhabits buildings in Central Europe without exception.
description
The spider reaches a body length of 4 to 6 mm. It is easy to recognize by its high bulging front body ( prosoma ), which is about the same size as the abdomen. After she has caught a prey with glue, the front body is much flatter with empty glandular chambers. Like all spiders in the family, Scytodes thoracica is six-eyed (two eyes in three groups) and has a sand-yellow to translucent basic color, on which dark-gray to black spots, which can have become stripes, can be seen. The darkly ringed, sand-yellow legs are very thin and can hardly be seen from a distance.
distribution and habitat
The food spider is widespread almost worldwide today. In addition to the southwest and southeast Palearctic , the species also colonizes western North America and has also been found sporadically in South America, Central Africa, Southeast Asia and Australia. In Europe the species is absent in the north and east, the northern limit of distribution runs through central England and Denmark; in the east the species is already absent in Poland.
Originally, the distribution area probably only comprised the subtropical zone, where the species occurs freely under stones. In Central Europe the species is synanthropic and can be found almost exclusively in older houses.
Way of life
The food spider is the only spider in Central Europe that overcomes its prey from a distance. It locates its prey with cup hairs (trichobothria) on the front pair of legs. It spits glue from transformed poison glands through enlarged chelicerae openings up to 20 millimeters wide onto its prey. The transformed, two-part venom glands have a storage chamber in the spider's front body, which is emptied by muscle contraction. The prey animals are stuck to the ground in 140 ms by the glue from the larger venomous gland chamber, which is spat out horizontally and vertically, about 20 times in a zigzag shape and precisely. Sometimes the chelicerae oscillate only horizontally or only vertically. The venomous bite then takes place with venom from the smaller gland and the prey is sucked out.
The males make a thread before copulation, which is then held by the third pair of legs and passed over the genital opening to collect the sperm . The sperm is then absorbed into the bulbs by thickening of the pedipalps (jaw palpation) . Finally, the bulbs are inserted into the sexual opening (without epigyne ) of the female. The female spins an egg sac that she holds in place with the chelicerae and carries around with her under the sternum .
Although it usually moves slowly and stealthily, it can also run quickly on walls and ceilings in the event of danger.
Danger
The species is widespread and common in suitable habitats. In Germany it is classified as "safe" in the Red List .
photos
Scytodes thoracica from the front
Scytodes thoracica from the side
Scytodes thoracica with fixed prey
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literature
- Heiko Bellmann : Cosmos Atlas Arachnids of Europe . 3rd edition Kosmos, Stuttgart 2006, ISBN 978-3-440-10746-1 .
- Rainer F. Foelix: Biology of the spiders. Georg Thieme Verlag, Stuttgart 1979, ISBN 3-13-575801-X
- Willis John Gertsch : American Spiders, 2nd edition. Van Nostrand Reinhold, New York 1979, ISBN 0-442-22649-7
- L. Watson, MJ Dallwitz 2004 onwards. The families of spiders represented in the British Isles. Version: 23rd October 2005
- 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. Nature conservation and landscape management in Brandenburg 8, booklet 2 (supplement); 1999.
Web links
Scytodes thoracica in the World Spider Catalog