Spiders make up the majority of the arachnida class (or arachnids), with over 50,000 known species. Mites come a close second at 48,200 species. The other arachnids are scorpions, whip scorpions, microwhip scorpions, pseudoscorpions, harvestmen and sun spiders. Most species are carnivorous.
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Deadly scorpion ID
Steve Backshall explains how to tell if a scorpion is deadly or harmless.
Steve Backshall explains how to tell if a scorpion is deadly or harmless.
Scorpion cornucopia
A roundup of the different shapes and sizes of scorpion from the Deadly 60 list.
A roundup of the different shapes and sizes of scorpion from the Deadly 60 list.
Face the Fear: Scorpion
Steve introduces Naomi to a Emperor Scorpion during Live 'n' Deadly in Norwich.
Steve introduces Naomi to a Emperor Scorpion during Live 'n' Deadly in Norwich. Watch out for those claws!
Creepy crawlies
Fossils show that spider- and millipede-like creatures once crawled over ancient Wales.
Fossils show that spider- and millipede-like creatures once crawled over ancient Wales.
Arachnids are a class (Arachnida) of joint-legged invertebrate animals in the subphylum Chelicerata. All arachnids have eight legs, although the front pair of legs in some species has converted to a sensory function, while in other species, different appendages can grow large enough to take on the appearance of extra pairs of legs. The term is derived from the Greek words ἀράχνη (aráchnē), meaning "spider".
Almost all extant arachnids are terrestrial. However, some inhabit freshwater environments and, with the exception of the pelagic zone, marine environments as well. They comprise over 100,000 named species, including spiders, scorpions, harvestmen, ticks, mites and Solifugae.
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