Age: Upper Silurian
Bertie Group, Fiddler Green Formation, Phelps Member
Locality: Herkimer Co., New York
You are looking at a member of one of the first animal groups to venture onto land.
For many hundreds of millions of years all life flourished in oceans. Around 400 million years ago this extinct group of arthropods known as eurypterids made their way into freshwater and onto land. Eurypterid fossils have been recovered from marine and freshwater deposits, and trackways attributed to them have been found in terrestrial rocks.
Eurypterids are arthropods, a group characterized by a segmented body and jointed appendages and an outer skeleton (exoskeleton) requiring that the animal shed its skeleton as it grows. Those shed skeletons are known as ‘molts’ and are often moved by currents into accumulations. This specimen is a single molt from such a collection. Some of the appendages are missing but the head (termed ‘Prosoma’), main body (‘Mesosoma’) and lower body (‘Metasoma’) within which the tail (‘telson’) is located, are well preserved. The two swimming legs are visible and one of six walking legs. The sockets for the compound eye are visible. It looks rather like a huge scorpion and they are often referred to as ‘sea scorpions’. The largest one ever found is 1.3 meters (4.27 feet) and is on display at the Paleontological Research Institution in Ithaca, New York.
Eurypterids are now extinct, but arthropods are a very important part of modern biodiversity. The familiar lobsters and crabs and the prolific insect world represent over three-quarters of the known animal life today.
This specimen was donated to the Museum by the Austin Paleontological Society in honor of the outstanding support given to the Society by Jean Wallace.