However, only bones from the animals right foot have been found, though a cast has been made of the animal. Dr. John Thurmon thinks Rayonnoceras would be a good state fossil. It is a straight-shelled nautiloid found in Carboniferous deposits of north Arkansas. Some Rayonnoceras fossils are several feet long. Dr. McFarland thinks a goniatite might be a good choice.
Goniatite fossils are common in northern Arkansas.
Arkanites relictus is a goniatite named for Arkansas. It is found in the Hale Formation, which dates to the Early Pennsylvanian Period. If you remember what a nautiloid is, then you have a pretty good idea what a goniatite is. Like nautiloids, squids, and octopuses, goniatites are cephalopods. They are members of a larger group of cephalopods called ammonoids.