Once again, I’ve noticed that a switch from paleontology to history-related material has resulted in my website views taking a nosedive. So, to appease the public, I am putting more prehistoric stuff on here.
Allow me to introduce Megalneusaurus. This creature was a large 25-foot marine reptile which lived in the Pacific Ocean along North America’s western coast as well in as the shallow Sundance Sea, which covered much of north-central North America, during the late Jurassic, approximately 155 MYA. It was a member of a group of animals called the pliosaurs, whose most famous members consisted of Kronosaurus and Liopleurodon.
So far, the only evidence that we have of this creature is what might be a single fragmentary skeleton discovered towards the end of the 19th Century consisting of some vertebrae, one flipper, a few ribs, and most of the pelvis. In 2007, scientists published a report in which they re-discovered the original locality where these bones were uncovered. Among the finds found were the stomach contents, consisting of the remains of belemnites – primitive squid-like creatures.
Since a complete or even reasonably-complete specimen of Megalneusaurus has not been found, paleo-artists have a slight degree of elbow room in terms of how this animal looked in life. This drawing is heavily-based upon an old and inaccurate illustration of a Liopleurodon skeleton from the 1960s(http://plesiosauria.com/images/line_drawings/liopleurodon2_newman&tarlo.jpg). Firstly, Liopleurodon’s skull was actually a bit flatter than shown in that drawing. It also had more teeth in its jaws – the old illustration shows only the front teeth. Finally, and most obviously, it is depicted with a short somewhat triangular tail fin. I kept the head’s structure more or less as it was, put more teeth in the jaws, and made the tail fin diamond-shaped to make it more symmetrical. It’s unknown whether or not pliosaurs like Megalneusaurus actually had a tail fin, but I kept it here since it looked interesting. Besides, until a couple of years ago, no one would have guessed that mosasaurs like Prognathodon would have had shark-like tail fins, but there you go, that’s paleontology for you.
Check out the two websites below for more information on this creature: