Turtles may have been described variously as tasting like veal, turkey, or fish, but a newly discovered species, dating back to around 76 million years ago, had something decidedly porcine about it. In fact, the snout on its nose was so pig-like, it’s been dubbed the “pig-fat” or “bacon" turtle, officially named Arvinachelys goldeni if you want to get technical. The fossil of the extinct animal was found in Grand Staircase-Escalante National Monument by a team from the Natural History Museum of Utah, and has been formally described in the Journal of Vertebrate Paleontology.
The turtle is thought to have lived in a swampy environment not too dissimilar to what is found in modern-day Louisiana, paddling around in the rivers, bayous and flood plains formed by the Western Interior Seaway that divided eastern North America from the west during the Cretaceous period. It would have shared the landscape with dinosaurs such as tyrannosaurs and the armored ankylosaurs, but also other animals that have changed little since then, like crocodiles and amphibians.
The turtle is unusual in the fact that the nasal cavity of the skull is divided by bone. Natural History Museum of Utah
One other species of living turtle has a fleshy porcine-like snout, the pig-nosed turtle from northern Australia, but this new fossil is unusual in the fact that its skull has two nasal openings, whereas all other turtles have only one. When they're alive, the nasal cavity is instead normally divided by soft tissue, but not so with this new find. This feature would no doubt have given the living animal a particularly piggy appearance.
The new species is especially well preserved, with the skull, shell, parts of the limbs and tail all intact, which is unusual for most ancient turtles found. This will hopefully let the researchers fill in some gaps when it comes to turtle evolution. “With only isolated skulls or shells, we are unable to fully understand how different species of fossil turtles are related, and what roles they played in their ecosystems,” explains University of Utah’s curator of paleontology Randall Irmis.
The fossil could help the researchers piece together how different species of turtle evolved and diverged during this period of time as the Western Interior Seaway divided animals on one side of America from the other. This pattern of species being separated is seen with other animals during the Cretaceous too, such as with dinosaurs that couldn’t cross the expanse of the massive inland sea.
By understanding what conditions in the past influenced species dispersal, survival, and their divergence, it could inform researchers as to how modern-day animals might react to the changing climate. Currently, the movement of animals is being restricted by an ever-expanding human population as well as by shifts in the environment.