Phylloneta impressa
| Phylloneta impressa | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Phylloneta impressa , male |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Phylloneta impressa | ||||||||||||
| ( L. Koch , 1881) |
Phylloneta impressa (brown and white or brown ball spider) is a species of spider from the family of the canopy web spiders (Theridiidae).
Appearance
The females of Phylloneta impressa reach a body size of 3.5 to 5.5 millimeters, the males only 3.5 to 4 millimeters. The front body ( prosoma ) is yellow-brown in color. There is a dark median on it. It widens slightly towards the eye area, but does not quite reach the eyes. The entire front body has a thin, dark brown border.
The spherical rear body ( opisthosoma ) has a white basic color. There is a broad, mostly reddish longitudinal stripe in the middle. To the side of it there are broad, dark brown to black longitudinal stripes. These are interrupted by three or four thin white horizontal stripes, which also point slightly backwards on the outside.
The legs are light brown and curled dark brown at the joints.
Similar species
Phylloneta impressa is very similar to some other species of the genus (e.g. Phylloneta sisyphia ) and is also found in very similar habitats. Therefore, in case of doubt, the species can only be reliably differentiated on the basis of the sexual organs.
distribution
Phylloneta impressa is widespread throughout the Holarctic . It prefers open and dry habitats and is usually not uncommon there.
Way of life
Phylloneta impressa builds a typical canopy network on plants that are not too high and that are otherwise free. The tip of the plant is spun with tangled threads. At the top in the middle, the threads are spun more densely, so that there is a hiding place that is open at the bottom and shielded at the top with the help of parts of plants. This is where the spider stays most of the time.
Catching prey
Spun in the net are sticky catch threads that are only loosely connected to the ground. If a prey insect gets caught on such a thread, it loosens and the prey dangles helplessly in the air. When trying to break free, the prey touches other catching threads and thus gets more and more entangled in the net. The alarmed spider rushes over and usually spins the prey even further before paralyzing it with a poison bite. The prey is then transported to the hideout and eaten there.
Brood care
After the eggs have mated and developed, the female builds a gray-turquoise egg cocoon and places it in the hiding place. There he is guarded until the young spiders hatch.
Phylloneta impressa is a specialty among the spiders. It is one of the few species that practices brood care that goes far beyond guarding the cocoon. After hatching, the young spiders stay in their mother's web for some time. During this time, the mother feeds them from mouth to mouth with a special nutrient fluid. This nutrient fluid is strangled out by the mother ( regurgitation ) and consists of pre-digested food and cells from the mother's intestines. The young spiders stimulate the mother by touching it to choke out the liquid, and several young spiders suck up the drop of the given food. This direct feeding of the young ends with the first molt of the young spiders.
In the further course, the offspring are no longer fed directly, but eat at the mother's prey. Only later are the young spiders driven from the mother's web and they spread in the area.
The feeding by the mother was verified by placing prey animals marked with radioactive phosphorus in the net after the cocoons were built. At first only the prey was radioactive, and after eating, so was the adult animal. The young that hatched later were not yet radioactive. Radioactivity was only detectable in both after the mother had fed the young.
Web links
Phylloneta impressa in the World Spider Catalog
swell
Individual evidence
- ↑ a b c d Heiko Bellmann : Cosmos Atlas Arachnids of Europe . 2nd Edition. Kosmos-Verlag, 2001, ISBN 3-440-09071-X .
- ^ Norman I. Platnick, 2007. The World Spider Catalog, Version 8.0. American Museum of Natural History.
- ^ A b c d Rainer F. Foelix : Biology of Spiders . 2nd Edition. Oxford Thieme, 1996, ISBN 0-19-509594-4 .