What Am I? Can You Guess?

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What Am I?Can You Guess?
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What is hidden behind these tiles?
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I am commonly found in Southern Arizona and in
parts of Texas and Central Oklahoma.  
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I live for two to ten years.  
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Females are usually bigger  
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I do not have good eyesight
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I sense my way around using sensory hairs and
slit organs on my legs
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I am one of 1300 different species
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I have eight legs
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I belong to the class of Arachnida
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I am venomous
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I am related to Spiders, mites,ticks
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I can be found as high as 12000 ft in the Andes
Mountains also in the Himalayas  
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I have special organs on the underside of my body
called pectines, which pick up ground textures
and scents
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I take a long time to reach maturity, moulting
frequently (up to five or six times over two to
six years)  
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When I meet another of my kind, we usually fight
until one of us is killed and eaten by the winner
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I am nocturnal
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I am a scorpion!