Equipped with powerful jaws and finely serrated teeth, paleontologists say the 43-foot-long prehistoric marine reptile deserves the name Tylosaurus rex.. The newly described predator, named Tylosaurus rex (or T. rex), measured up to 43 feet long and ranks among the largest mosasaurs ever discovered.
Paleontologists have described a gigantic new species of mosasaur -- stretching up to 13.2 m (43 feet) long and armed with serrated teeth -- and given it an unexpected name: T. rex (short for Tylosaurus rex).. There's a newly crowned T. rex. This one, called Tylosaurus rex, was a tyrant of the sea and mosasaur spanning up to 43 feet in length.