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| | | Spiders (Araneae) | | Araneae are frequently referred to as „true spiders“ or simply as “spiders”. There are approximately 40,000 species globally, in 3,700 genuses (people will know more easily what you mean) and 108 families. Araneae have 8 legs in contrast to insects which have 6. Furthermore instead of compound eyes they have 8 simple eyes. | | |
| | | | The head and chest form one unit (Prosoma). This is followed by the abdomen which is usually significantly bigger. Araneae are Chelicerata. At the end of the head are retractable claws, containing glands which secrete poison. They do not use theit mouthparts (at the male as genitals) for chewing their food. Four pairs of legs are attached to the prosoma and each leg comprises six to seven segments, which in addition to the hairs on their legs build an important sensor system. | | |
| | | | The life expectancy of spiders varies. The growth of the body is severely limited by a rigid external skeleton. When Araneae want to shed their skin they retreat into hiding and stop eating. While most spiders hang from a thread while they are shedding their skin, tarantulas lie on their backs. | | |
| | | Almost all spiders are land animals. They often hide during the day and are only active at dawn or at night. The water spider is the only genus which lives in water. A number of species hunt on the water surface.
Birds pose the biggest threat to spiders. However amphibians, reptiles and bats also eat spiders. Some spider species feed exclusively on other spiders. Other natural enemies are: wasps, ants, true dragonflies, small-headed flies, Nematodes and Acarina. | | |
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| | Further chapters of "Spiders" | |
| | Description of images / photos | | 1. | Spider - Zygielle x-notata - at cobweb | | 2. | Spider - European garden spider on its cobweb | | 3. | Spider | | 4. | Spider - Araneae |
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