The Graneros Shale is a rock unit formed in the Late Cretaceous Western Interior Seaway of North America. In this study, I report an assemblage of fossil vertebrates from the middle portion of the Graneros Shale in southeastern Nebraska. The estimated age of this fauna is about 97 million years old, and it is dominated by carnivores that consist of at least 11 taxa, comprising of eight sharks, one bony fish, and two reptilians (turtle and plesiosaur). The fauna includes taxa indicative of a nearshore, but fully marine, environment that do not contradict with previous paleoenvironmental inferences made for the Graneros Shale. This study is important because it represents the first collective faunal study of fossil vertebrates from the mid-Graneros Shale at a single locality.
Meglei, Alexander D.
"Fossil Marine Vertebrates from the Middle Part of the Upper Cretaceous Graneros Shale in Southeastern Nebraska,"
DePaul Discoveries: Volume 2, Article 6.
Available at: https://via.library.depaul.edu/depaul-disc/vol2/iss1/6