Washington, Feb 27 : The fossil of a massive ancient sea reptile dubbed as "T-Rex of the Ocean", which was discovered on a remote Arctic island in 2006, has been determined to be the largest marine reptile ever known.
The finding was made in permafrost among a prehistoric "graveyard" of large marine reptiles approximately 800 miles (1,300 kilometers) from the North Pole, by a team led by Jorn Hurum of the Natural History Museum in Oslo, Norway.
According to a report in National Geographic News, the giant reptile, dating back to 150 million years, measured some 50 feet (15 meters) in length.
It was first discovered in 2006 on Spitsbergen, part of Norway's Svalbard archipelago, in a polar wasteland littered with fossilized sea reptiles
"We knew immediately this was something special," said Hurum. "The large pieces of bone and the structure of the fragments told us that this was big," he added.
The team recovered a large chunk of the skeleton, including portions of its estimated ten-foot-long (three-meter) skull, an almost complete forelimb, and sections of its dinner-plate-size vertebrae.
Dubbed "the Monster," it's thought to be a previously unknown species of plesiosaur.
"It's as big or bigger than the largest plesiosaur ever found," said Hurum. "This absolutely looks like a new species," he added.
Plesiosaurs were marine reptiles that typically had small heads, long necks, and large flippers.
But the newfound plesiosaur is thought to have been a pliosaur, and pliosaurs were different from other plesiosaurs.
With short necks and massive heads, pliosaurs became the top marine predators during the Jurassic period, 200 to 145 million years ago.
According to Hurum, the newly excavated specimen is 20 percent bigger than what was until now the largest known pliosaur, Kronosaurus from Australia.
Calling the latest find "the T. rex of the ocean," Hurum said it "would have eaten other marine reptiles and maybe some of the huge bony fishes that were around at that time."
The creatures swam in temperate seas and sank to the ocean floor after they died, where their bodies were preserved in soft mud.
"Not only is this specimen significant in that it is one of the largest and relatively complete plesiosaurs ever found, it also demonstrates that these gigantic animals inhabited the northern seas of our planet during the age of dinosaurs," said Patrick Druckenmiller, a plesiosaur expert at the University of Alaska's Museum of the North.