First elasmosaurid plesiosaur from Montana announced

Elasmosaurid plesiosaurs are notorious for ‘losing their heads’. In fossil plesiosaur skeletons the skull is frequently missing, unfortunate because this is such a vital part of the anatomy for understanding the relationships and biology of the animal. This fact makes the discovery of a new elasmosaurid skull, the first ever from the state of Montana, all the more significant.

In addition, the new skull is well preserved. Dr Pat Druckenmiller of Montana State University who will be describing the fossil explains -“The new long-necked plesiosaur (elasmosaur) skull is one of the nicest of its kind known from North America. It is unusual in only being slightly crushed; what crushing is present has occurred from from top-to-bottom, not side-to-side, which is unusual and can tell us about parts of the skull that are usually totally messed up…the jaws have only a minimal amount of damage, and are almost completely uncrushed.”

This unusal preservation should also provide important rare data on the structure of the skull. “CT scanning (courtesy of Bozeman Deaconess Hospital) also provides insight into the interior of the skull, such as the braincase.” Druckenmiller said, concluding that “its completeness, relatively small degree of crushing, and quality of preservation makes it one hot skull!”

The skull is from the Late Cretaceous Bearpaw shale, a sequence of 70 million year old marine deposits, and will eventually form part of an exhibit in the Museum of the Rockies.