The Graneros Shale was deposited in the Late Cretaceous Western Interior Seaway of North America during the mid-Cenomanian (ca. 95 Ma). Vertebrate fossils are known to occur in the rock formation, but there is no detailed report collectively documenting the composition of the vertebrate fauna. In this study, we collected many remains of fossil fishes from the uppermost portion of the Graneros Shale in southeastern Nebraska. The fish fauna consists of at least 14 chondrichthyan and 10 osteichthyan taxa. The locality is characterized by the abundance of benthic taxa, indicative of a well-oxygenated, shallow marine environment. This paleoenvironmental inference based on fossil fish evidence is consistent with that made previously for the Graneros Shale based on lithological and invertebrate evidence.
Western Interior Seaway