Eurypterids are sometimes called “Sea Scorpions”. They are arthropods that lived from the Ordovician to the great Permian Extinction but reached their zenith during the Silurian. They are well known for their scorpion like appearance but are not scorpions, they are closely related to Horseshoe Crabs. They were quite formidable predators.
The Eurypterids inhabited shallow seas and lagoons. As arthropods they had a hard dorsal exoskeleton and jointed legs. They are easily identified by the long tail spine or telson. The largest recorded was over 7 feet long. Rarely are they ever found complete. Most assemblages are discarded exoskeletons as they molted. The molts washed close to shore, into depressions and then were covered by sediment.
Eurypterus remipes is the state fossil of New York State and is found at a location in Illion, New York.
Many of the specimens seen in museums and for sale come from the famous Lang’s Quarry owned by R.A. Langheinrich.
The smallest Eurypterid is 1 3/4 inches long and has walking legs visible. The telson is on the body of the one under it which is 2 1/4 long. It has 1 paddle. The one by itself is 2 3/4 amidst a jumble of paddles and legs. There is the head and 2 paddles of a fourth on the plate as well. This matrix block is 6 inches by 4 3/4 inches.
Fiddlers Green Formation
Illion, New York