: any of an order (Eurypterida) of usually large aquatic Paleozoic arthropods resembling scorpions and related to the horseshoe crabs. — called also sea scorpion.

What does the fossil of a Eurypterid represent?

Eurypterid coprolites discovered in deposits of Ordovician age in Ohio containing fragments of a trilobite and eurypterid Megalograptus ohioensis in association with full specimens of the same eurypterid species have been suggested to represent evidence of cannibalism.

How do you spell Eurypterid?

any aquatic arthropod of the extinct order Eurypterida, from the Paleozoic Era, closely related to trilobites and scorpions.