Scorpions are predatory arachnids of the order Scorpiones. They have eight legs and are easily recognised by the pair of grasping pedipalps and the narrow, segmented tail, often carried in a characteristic forward curve over the back, ending with a venomous stinger. Scorpions range in size from 9 mm (Typhlochactas mitchelli) to 23 cm (Heterometrus swammerdami).