When it comes to the world's largest marine reptile, many people may first think of Liopleurodon of the Pliosauridae family. In fact, the largest Liopleurodon was only 15 meters. Canadian paleontologists once discovered a 21-meter-long Shawnee ichthyosaur fossil in the Late Triassic strata of British Columbia, setting a new record for the largest ichthyosaur. But this record has been broken by the 23-meter-long Sasta Ichthyosaurus fossil and the 25-meter Pink Mountain Ichthyosaurus discovered in Canada in recent years.

Shawniichthyosaurus is a giant ichthyosaur that appeared in North America in the late Triassic. Its length generally reached about 15 meters. The most special thing is that its four fins are very large and almost equal in length. In addition, it has a fat belly, which can be called "the best among fish and dragons".