9781422278260

separates them from other arachnids, includ- ing scorpions, false scorpions, harvestmen, ticks, mites, whip scorpions, sun scorpions, and a few other minor groupings. Spiders are an extremely diverse group in terms of appearance and the number of spe- cies; there are more than thirty thousand spe- cies known to science at present and many more yet to be described. With such a scope as this, it would be impossible to cover spider classification comprehensively in a book of this size. The brief survey of the range of spiders that follows will, however, provide a useful background to their taxonomy. For the purposes of this book, two suborders are con- sidered; these comprise the majority of spe- cies including those most familiar to spider enthusiasts.

pumping, and the split continues down the sides of the abdomen. The spider eventually extricates its legs and pulls itself free. There is a degree of flexibility in the new cuticle which allows expansion in body size to occur, but the process often has to be repeated many times during its life before a spider can achieve its full size. Not surprisingly, the spider is extremely vulnerable during the process of molting. It is usually performed while sus- pended on a silken thread, and often under the cover of darkness. Classification The relationship between spiders and their Arthropod cousins has been discussed previ- ously, spiders belonging to the class Arachnida and the order Araneae; this latter subdivision

The banana spider is found in the Amazon rain forest in Peru. Its large size enables it to catch comparatively large prey such as katydids and cockroaches.

Suspended in its elegant web, a golden-silk spider or calico spider, Nephila clavipes, awaits the arrival of an unsuspecting prey such as a butterfly.

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