General

General

Spiders belong to the kingdom Animalia and the phylum Invertebrate. This classification of spiders in to invertebrates pertains to their lack of spinal cord. They belong to the class Arachnida and order Araneae. There are about 40,000 species belonging to different families and genre based on their evolutional status. Spiders which have been classified till date are placed under three suborders, thirty eight super families and hundred eleven families. The three major sub orders are based on the segments and the movement of the jaws. Sub order Mesothelea are characterised by segmented plates on their abdomen and found in scarce quantities. They are the primitive spiders which dwell by burrowing and include Arthrolycosidae, Arthromygalidae and Liphistiidae. Sub orders Mygalomorphae have no segmentation on their abdomens. They are distinguished by their heavy built, hairy abdomens and large robust fangs. These include the Goliath Birdeater, Tarantulas, mouse spider and many more. The last of the suborders is the Araneomorphae which includes brown recluse, Tasmanian cave spiders and a number of other species. It is the largest suborder of the order Arachinidae and sum to more than 90% of the spiders. They are called the true spiders.

Endangered and pet spiders

Some of the species of spiders are wild and dangerous to the humans. This pertains to the venom which they discharge from the glands on biting. Though all spiders have significant amount of venom, very few have toxic levels sufficient to cause infections and at times cause death. Few such species are the Black widow spider. Tarantulas, wolf spiders are few species which are kept as pets for their harmless behaviours and serene methodology of living. They do not mess about the cage and can be easily tamed.

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© PaulSteinJC „Spider on a Flower“
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