Check out these 10 truly terrifying prehistoric monsters of the deep that roamed the ancient oceans millions of years ago.\r
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- Mega Top Tens\r
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10 Terrifying Prehistoric Sea Monsters\r
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Some of the largest creatures this world has ever seen lived millions of years ago. Here are ten of the largest, most fearsome sea monsters ever to prowl the oceans.\r
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Dakosaurus was first discovered in Germany and, with its odd reptilian-yet-fishy body, was one of the top predators in the sea during the Jurassic period.Fossil remains have been found across a very widespread distribution, turning up everywhere from England to Russia to Argentina. Though it is commonly compared to modern crocs, Dakosaurus could reach a length of 16 feet (5m). Its unique teeth have led scientists to consider it an apex predator during its reign of terror.\r
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Tylosaurus was a species of Mosasaur. It was enormous, reaching more than 50 feet (15m) in length.The tylosaurus was a meat eater with a very diverse diet. Stomach remains show signs of fish, sharks, smaller mosasaurs, plesiosaurs, and even some flightless birds. They lived during the late Cretaceous in the seas that covered North America, where they sat firmly atop the marine food chain for several million years.\r
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Only recently discovered, T. saurophagis was the size of a school bus, reaching nearly 30 feet (9m) long. It is an early species of ichthyosaur that lived during the Triassic period, 244 million years ago. Because they were alive shortly after the Permian extinction (Earths largest mass extinction, when 95% of marine life is thought to have been wiped out), its discovery is giving scientists new insights into the quick recovery of the ecosystem.\r
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While Tanystropheus was not strictly marine, its diet was mainly fish and scientists think it spent most of its time in the water. Tanystropheus was a reptile that could reach 20 feet (6m) long, and it is thought to have been alive during the Triassic period nearly 215 million years ago.\r
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Liopleurodon was a marine reptile measuring in at more than 20 (6m) feet in length. It mostly lived in the seas that covered Europe during the Jurassic period, and it was one of the top predators around. Its jaws alone are believed to have been over 10 feet long – roughly the distance from the floor to the ceiling.With teeth that big, its easy to see why Liopleurodon dominated the food chain.\r
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If the Liopleurodon was huge, than Mosasaurus was colossal.Fossil evidence suggests that Mosasaurus could reach as much as 50 feet (15m) in length, making it one of the largest marine predators of the Cretaceous period. Mosasauruss head was like that of a crocodile, lined with hundreds of razor sharp teeth which could kill even the most well-armored enemies.\r
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One of the largest predators in marine history and one of the largest sharks ever recorded, Megalodons were as terrifying as they came.Megalodons prowled the depths during the Cenozoic Era, 28 – 1.5 million years ago, and were a much bigger version of the great white shark, an apex predator of todays oceans. But while our great whites only reach a maximum length of 20 feet (6m), Megolodons could grow to 65 feet in length (20m) – longer than a school bus!