The shell was coiled into a flat spiral and was characterized by a series of ridges and spines along its surface

it did have a small bony protrusion in the nasal region

Secodontosaurus willistoni was a medium-sized animal

Pakicetus inachus is a species of prehistoric cetacean that lived approximately 50 million years ago

Although Pliosaurus funkei was an agile and powerful swimmer

Livyatan melvillei Lystrosaurus The shell was coiled intoLivyatan melvillei is an extinct species of predatory cetacean that lived during the Miocene, approximately 12 13 million years ago. It is named after Leviathan, a mythological sea creature mentioned in the Bible, and Herman Melville, the author of the novel "Moby Dick." This cetacean belonged to the sperm whale family, but differed in several key aspects from modern sperm whale species. Outstanding features of Livyatan melvillei: Impressive size: