Our field jackets from Carmel Church have loads of bone in them, from a variety of different animals. This is true even when the jacket has been made to collect a single element like a skull. As an example, the jacket containing the skull of “Picasso” has so far produced remains from at least 19 different vertebrate species (plus “Picasso” itself). Most of these are sharks, bony fish, and whales, but some of the things are a little different.
The vertebra shown above was sitting under “Picasso’s” skull; since we opened the jacket from the bottom, we found this vertebra early in the preparation. As soon as it was uncovered I thought it looked a little odd for a whale, and as I looked at it more closely I saw some features that ruled out whales. One of the most prominent was a deep triangular fossa (a depression) at the base of the neural spine on the anterior margin, shown in the closeup below; this is an oblique view with low-angle lighting to make the fossa more visible:
We don’t have any other vertebrae like this in our collection, but when I attended the SeAVP meeting at the South Carolina State Museum last month (was that really only a month ago?) I was able to confirm that this vertebra is from a sirenian (a sea cow). The only recognized sirenian from the Calvert Formation is the dugongid Metaxytherium crataegense. We’ve already found several sirenian ribs at Carmel Church which are consistent with Metaxytherium, but this is the first sirenian vertebra we’ve recovered.