Name Meaning:  Cretaceous Lamna (fish of prey) Geologic Era:  Cretaceous to Miocene

Estimated Range:  Worldwide (this species primarily found in Morocco) Location Found:  Morocco

Size:  Between 2-3 meters long (largest is 3.6 meters in length)

Extinction:  Mid Miocene (13.65 million years ago)

This shark lived both before and after the dinosaurs, surviving the K-T extinction that wiped out not only the dinosaurs, but a great deal of marine life as well.  This implies that Cretolamna sharks were very adaptable, as they would have had to transition from eating large marine reptiles and fish to fish and marine mammals.  This tooth probably came from a shark on the smaller end of the size range, maybe a meter or so long.  This shark’s teeth were designed to deal with large prey, as seen by the small cusps on either side of the main tooth.  These cusps would have helped the shark grip and tear into prey.  This does not mean that Cretolamna was the top predator in its environment.  At most times during its stay on Earth, Cretolamna would have been in competition with much larger sharks and mosasaurs, and ultimately some of the larger predatory whales.

While Cretolamna itself might be extinct, it’s descendants live on in the form of other lamniform sharks such as Great Whites.  Cretolamna may also have been the ancestor of other, larger sharks such as Otodus and C. megalodon.  In terms of behavior, Cretolamna was probably similar to a modern Great White, inhabiting both coastal and open waters, and being a predator of opportunity.  It would have preyed on nearly anything smaller than it was, which, depending on the time, could have been marine reptiles to mammals.  There is no guarantee that this tooth is an indicator of how large this particular shark actually grew, as sharks continually shed and replace teeth through their lives.  This tooth might have been shed while the shark was still relatively young.

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