Scorpions are predatory arachnids of the order Scorpiones. They have eight legs, and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always ending with a stinger. The evolutionary history of scorpions goes back 435 million years. They mainly live in deserts but have adapted to a wide range of environmental conditions, and can be found on all continents except Antarctica.

Scorpions glow a vibrant blue-green when exposed to certain wavelengths ranges of ultraviolet light such as that produced by a black light, due to fluorescent chemicals such as beta-carboline in the cuticle.

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