Tylosaurus (Tie-low-sore-us) - A genus of giant mosasaur, a formidable marine reptile known from the Late Cretaceous. Several species have been described, and some, such as Tylosaurus proriger grew to more than 12 metres in length. American palaeontologist Othniel Charles Marsh proposed the genus in a short note published in the American Journal of Science and Arts in 1872. The naming had been complicated because earlier names suggested for this animal, such as Rhinosaurus and Rhamphosaurus, were already being used for other reptiles. The front of the snout was long and toothless, forming the distinctive “knob” or “protuberance” that inspired its name. Fossil skulls show damage to this area, suggesting Tylosaurus may have rammed prey with its snout to stun or injure them or even used it when fighting other members of its own kind. dimensions: 20.5cm x 4.8cm
