![]() My hunch- though it was nothing more than that- was that there were more plesiosaur fossils to be found, and we should look for them. It seemed possible that this little bone from a plesiosaur flipper was a one-off, a fluke. What’s a plesiosaur doing in the Kem Kem? ![]() Plesiosaurs more rarely show up in brackish or estuarine settings, and even more rarely, in freshwater. You find them shales, sandstones, limestones and chalks laid down in Mesozoic seas. And those animals, like the vast majority of plesiosaur fossils, come from marine rocks. These are animals like the giant predators Kronosaurus and Liopleurodon, the ultra-long-necked Elasmosaurus, the long-snouted Dolichorhynchops. And since then, over a hundred species of plesiosaur have been discovered. We know that because they’re full of fossils of marine animals, like ammonites and belemnites. It’s as if the design of the animal was handed over to a small child, who proceeded to draw the anatomy in crayon.Īnyway, the beds in Lyme Regis that produced Plesiosaurus are marine rocks. They have a remarkably simplified structure. The individual bones of a plesiosaur skeleton are also very weird compared to other reptiles. In Anning’s sketch you can also see a number of features of their distinctive anatomy- blocky, triangular limb bones, dozens of bones in the fingers and toes to support those long paddles. The diversity and sheer size of some of these fish suggests that this river system was highly productive, and very large. These include huge lungfish, giant coelacanths, bowfin, freshwater-tolerant sharks and rays, frogs, salamanders, turtles, crocodilians, and a huge aquatic dinosaur, Spinosaurus. In the sands and clays laid down by those rivers, we find a rich fauna of fish and other aquatic animals. A vast system of rivers flowed north out of Africa and emptied into the Atlantic Ocean. It’s freshwater, an ancient, Cretaceous-aged river system.ġ00 million years ago, the Sahara of Morocco was a very different place. And plesiosaurs really shouldn’t be there, because the Kem Kem wasn’t deposited in the sea. This was a plesiosaur- a marine reptile- but it was in the Kem Kem beds. The image of those strange plesiosaur bones was still fresh in my head, and I was hit with recognition. ![]() I probably wouldn’t have paid it any attention, but the day before I’d been looking at a fairly complete plesiosaur skeleton from the Turonian of the Akrabou Formation. ![]() mixed in amongst various fossils, in a small rock shop in Erfoud, on the edge of the Sahara. The fossil in question was a triangular hunk of bone. ![]()
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