Placenticeras meeki ammonite specimen

This Placenticeras meeki ammonite specimen from the USGS Campanian Pueblo, Colorado Shale collection is now at the Smithsonian National Museum of Natural History where it will become part of their new Paleobiology display of fossils from the Upper Cretaceous. A showpiece in our Denver collections for decades, this specimen was a favorite with visiting scientists and hordes of school kids because of the paired bite marks clearly visible on both sides of the shell. The bite marks are attributed to a Mosasaur, the swimming reptile whose fossil remains are also found along the Colorado Front Range.