Mosasaurus was a fearsome marine reptile from the Late Cretaceous period, reaching lengths of up to 56 feet (17 meters). Characterized by its powerful jaws filled with sharp, conical teeth, it was an apex predator that hunted large prey, including fish, sharks, and even other marine reptiles like plesiosaurs. With a streamlined body and strong flippers, Mosasaurus was an agile swimmer, capable of quick bursts of speed to ambush its prey. Its elongated skull and large, serrated teeth were perfect

The coelacanth, a fish found in prehistoric fossils, was long thought to be extinct until one was caught in 1938. This discovery begged the question: if the coelacanth was hiding in plain sight for so long, could the loch ness monster be too? | National Geographic TV