Predatory Arachnid Invertebrate Scorpion Has Dangerous Polypeptide Neurotoxin Venom on Sting

Scorpions are predatory arachnid invertebrates of the order Scorpiones, recognizable by their eight legs, pair of grasping pincers, and a segmented, venomous tail that curves over their back. Found worldwide in diverse habitats, they are mostly nocturnal and use their venom primarily to kill prey, with only about 25 of the ~1,500 species possessing venom lethal to humans. Scorpions are arachnids with eight legs (four pairs) attached to their cephalothorax (combined head and thorax). As members of the Class Arachnida, they are closely related to spiders, mites, and ticks, rather than insects, which have six legs. These legs are segmented and covered in sensitive hairs used to detect vibrations and prey. Scorpions are among the most ancient terrestrial animals, having evolved over 400 million years ago.