(Late Cretaceous)

Dakotaraptor was a mid-sized carnivorous theropod dinosaur discovered in the South Dakota region of the Hell Creek Formation. At an estimated 16 feet in length from nose to long feathered tail, the Dakotaraptor bridges the gap between the gigantic tyrannosaurids like the T. Rex and smaller theropods like the Pectinodon. The Dakotaraptor is the second largest raptor species discovered, only dwarfed by the Utahraptor.

Pterotrigonia thoracica (Late Cretaceous)

Did you know Tennessee has a state fossil? Pterotrigonia thoracica was a bivalve that lived in the shallow seas that covered much of the middle of North America during the Cretaceous (Western Interior Seaway). Pterotrigonia thoracica was chosen as the state fossil due to its abundant fossils found in the Coon Creek Formation in West Tennessee.

Plesiosaurs (Late Triassic – Late Cretaceous)

Plesiosaurs were marine reptiles that lived during the age of the dinosaurs. Though not a dinosaur itself, Plesiosaurs are well-known for their distinctive body shape which inspired the famous cryptid, the Loch Ness Monster. While many believers argue that a Plesiosaur could still be in Loch Ness in Scotland, they unfortunately all went extinct at the same time at the non-avian dinosaurs following the K-Pg Impact. Their diet was comprised of fish and cephalopods. Plesiosaurs came in different shapes and sizes; some where large and long-necked like the Zarafasaurus oceanis who were generally pacifistic and solitary animals, while some like the Pliosaurus had short necks and large heads and were much more aggressive hunters.

The first complete Plesiosaur fossil was found by famous female paleontologist Mary Anning in 1823.

 Toxochelys (Late Cretaceous)

Toxochelys was a genus of sea turtle that live in the Western Interior Seaway, and its fossils are found in the United States and Canada. Toxochelys lived a similar life as modern sea turtles, feeding mostly on jellyfish, squids, mollusks, crustaceans, and marine vegetation. However, Toxochelys was larger, growing up to 6 feet in length.

This specimen was found by museum staff in the Coon Creek Formation in Tennessee.