Atlantic horseshoe crab

Atlantic horseshoe crab. They get their name from their general horseshoe shape. They have a hard exoskeleton like a crab. They are brown with a slender pointed tail. Unique looking, with nothing else that looks much like them in existence today. They like to eat clams, and worms.
Interesting fact--The species is estimated to be at least 300 million years old. They are more closely related to spiders and scorpions than crabs. Horseshoe crabs can swim upside down in the open ocean using their dozen legs and five book gills (which are hiding nearly 200 flattened gills) to propel themselves. They have 2 compound eyes on the top of their head and also 10 'eyes' that let them see UV light. Horseshoe crabs have blue blood.