A new mid-Silurian aquatic scorpion—one step closer to land?

  title={A new mid-Silurian aquatic scorpion—one step closer to land?},
  author={Janet B. Waddington and David M Rudkin and Jason A Dunlop},
  journal={Biology Letters},
One of the oldest known fossil scorpions, a new species from the mid-Silurian Eramosa Formation (430 myr) of Ontario, Canada, exhibits several surprising features. The depositional environment and associated biota indicate a marine habitat; however, the leg morphology of this scorpion, which has a short tarsus in common with all Recent scorpions, suggests that a key adaptation for terrestrial locomotion, the ability to support its weight on a subterminal ‘foot’, appeared remarkably early in the… Expand
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