Terrestrial Tetrapods In The Western Interior During The Cenomanian-Santonian

[DD1991]

While doing a search at Paleobiology Database, I was curious to see if I might find records of marine vertebrates from the Cenomanian-Santonian of the Utah, Montana, Idaho, and Arizona because most tetrapods found in the Cenomanian-Santonian of Nebraska, Kansas, and the Dakotas are primarily mosasaurs, plesiosaurs, pterosaurs, marine turtles, and seagoing birds (e.g. Ichthyornis, Hesperornis) and terrestrial vertebrates have been found in the Western Interior dating from the Cenomanian-Santonian interval (e.g. Oryctodromeus, Eolambia, Sonorasaurus, Albanerpeton cifellii, Nothronychus graffmani, various species of mammals like Ameribataar, and terrestrial lizards). Given the paleogeography of North America during the Cenomanian, would it reasonable to assume that Cenomanian terrestrial tetrapods retreated farther west into areas of Utah, Arizona, Idaho, and Montana that were not covered by the Western Interior Seaway to escape rising sea levels?

[Xiphactinus]

I know that the dino and associated fossils of Missouri are Cretaceous, but I'm not sure exactly what part of the period.

http://www.bcmnh.org/missouridinosaurstory.html

[DD1991]

I know that the dino and associated fossils of Missouri are Cretaceous, but I'm not sure exactly what part of the period.http://www.bcmnh.org/missouridinosaurstory.html

All dinos and associated fossils found in Missouri are of Late Cretaceous age and date back 65-70 million years, exactly the same time as T. rex, triceratops, and ankylosaurus.

[Ridgehiker]

I know that the dino and associated fossils of Missouri are Cretaceous, but I'm not sure exactly what part of the period.http://www.bcmnh.org/missouridinosaurstory.html

Thanks for the link...interesting story.

Odd, however, how these were not identified as Hadrosaur from the beginning...very distinctive. The preservation looks like they could have come out of the Alberta badlands. But then again, no Internet or Fossil Forum back then.