It was all in the teeth. Scientists have identified an entirely new extinct shark based on the ancient species' chompers gathered in the US, Japan, and Peru, UPI reports. A study of the "elusive" sea swimmer published Monday in the Historical Biology journal describes the great white-like Megalolamna paradoxodon as likely having lived in shallow coastal waters and, based on its tooth size, averaged about 13 feet in length (though some may have grown as large as 24 feet). And Kenshu Shimada, the lead author of the study out of DePaul University, is calling it "remarkable that such a large lamniform shark with such a global distribution had evaded recognition until now," a press release notes. The teeth, which were up to 1.8 inches long, were found in California and North Carolina, as well as overseas.
The shark lived about 20 million years ago during the Miocene era, scientists believe. And because its teeth—which consisted of "grasping" teeth in the front and "slicing" teeth in the back—resembled not only those found on other Otodontidae sharks (of which the also-extinct megalodon shark was also a member), but also seemed to be larger versions of those of lamniform sharks (which include today's mako sharks and great whites), the scientists created an entirely new species just for this creature. Science Daily explains that's why "paradoxodon" is part of the shark's name, as its teeth are "paradoxical." The scientists' other taxonomical conclusion: the super-predator megalodon should be moved from the Carcharocles genus to the Otodus genus. (Whales blew up in size after the megalodon went extinct.)