Proscorpius

Proscorpius (meaning 'dawn scorpion') is an extinct genus of proscorpiid scorpion that was originally thought to have been a eurypterid. Proscorpius lived during the Silurian and Devonian periods (about 422.9–416.0 ma). The type and only species, Proscorpius osborni is currently the world's oldest scorpion. It was discovered in the Lagerstätte Bertie Formation (Fiddlers Green Member); an epifaunal stratum of New York. The fossil measures roughly 3.8 cm (1.5 inches) in length, however, it is missing part of the tail, so in life the animal would be slightly longer.