This colossal prehistoric turtle could snap other turtles in half

For a brief period after the dinosaurs vanished, truly gigantic reptiles like the 50-foot snake Titanoboa and twenty-foot crocodiles dominated the swamps of ancient Colombia. Now we've discovered another, much gentler giant - the humongous 60-million-year-old "coal turtle."

First discovered in 2005, Carbonemys cofrinii takes its coal-themed names in both English and Latin from its discovery site, a coal mine in the Cerrejon formation of northern Colombia. A shell and a skull were found in close proximity, and while we can't yet be 100% sure that the two came from the same specimen, or even the same species, but their proportions do roughly match up, and those proportions are massive - the head would have been almost the size of a football, and the shell was over five and a half feet in diameter, a good foot and a half longer than any turtle species.

Carbonemys was one of a number of super-sized reptiles that took over ancient Colombia in the wake of the dinosaurs' extinction. Exactly why such megafauna took hold in this corner of the world only a few million years after such a giant mass extinction event isn't known for certain, but it was likely a combination of reduction in total predators, plentiful food, an enlarged habitat area, and other factors that allowed these species to evolve and unleash their inner leviathan.

While this turtle would have probably been a friendlier neighbor than a 50-foot snake - admittedly, just about anything would be - but you still would have wanted to give Carbonemys a very wide berth. The creature's jaw was incredibly strong, allowing it to devour passing crocodiles and even other turtles, as researcher Dr. Dan Ksepka explains:

"It's like having one big snapping turtle living in the middle of a lake. That turtle survives because it has eaten all of the major competitors for resources. We found many bite-marked shells at this site that show crocodilians preyed on side-necked turtles. None would have bothered an adult Carbonemys, though — in fact smaller crocs would have been easy prey for this behemoth."

For more on this story, check out Brian Switek's unsurprisingly excellent piece over at Wired.

Original paper at the Journal of Systematic Paleontology. Artwork by Liz Bradford.