Sea Urchin Fossil from Mammoth Cave

The state of Kentucky is famous for longest known cave system in the world called Mammoth Cave.  The cave is thought to have begun forming about 10 million years ago.  Located in Edmonson County, the cave system has over 350 miles of surveyed passages.  A national park preserves the cave for visitors to explore and enjoy.  Visit their web site as this link.

This sea urchin fossil was found there and has been identified as a Melonechinus indianensis from the Mississippian Period.  The stratigraphy found at Mammoth Cave are: Girkin Formation, St. Genevieve Limestone and St. Louis Limestone.  Other fossils found at the cave include shark teeth, blastoids, crinoids, horn corals, brachiopods, and snails.  Since it is a national park, collecting is prohibited!

The fossil pictured in this post was on display in 2010 at the Smithsonian National Museum of Natural History.