Horseshoe Crabs

Horseshoe crabs are for a fact one of the oldest species on earth who has been roaming around on this planet since the Ordovician period which was 445 million years ago. During that time the continents were not formed and there was single supercontinent called Gondwanaland and horseshoe crabs lived on the shore in abundance. Even today, these prehistoric species live in abundance. Where, you ask?