marine

Serratolamna

Serratolamna was a genus of prehistoric shark which lived from the late Cretaceous Period to the Eocene Epoch of the Paleogene Period, approximately 75-45 million years ago. The genus is currently divided into several species, of which the species S…. Read More ›

Cimoliasaurus

Cimoliasaurus, meaning “chalk lizard” due to its fossils being found within layers of chalk, was a genus of elasmosaurid plesiosaur which lived at the end of the Cretaceous Period 70-66 million years ago, making it one of the last plesiosaurs… Read More ›

Mosasaurus

Mosasaurus was a genus of fully-aquatic marine lizards which lived throughout the world’s oceans during the late Cretaceous Period approximately 75-66 million years ago. Fossils of this animal were first discovered in 1764 within a chalk mine in the town… Read More ›

Thalassomedon

Thalassomedon, meaning “lord of the sea”, was a 38 foot long elasmosaurid plesiosaur which lived within the Mowry Sea, the shallow sea that covered North America during the middle of the Cretaceous Period 97-95 million years ago. In March 1939,… Read More ›

Brachauchenius

Brachauchenius was a 15 foot long pliosaur which lived in the shallow sea that once covered the middle of North America during the middle Cretaceous Period 100-90 million years ago. Fossils of this animal were first found by Charles H…. Read More ›

Strophodus

Strophodus was a 10 foot long hybodont shark which specialized in eating shellfish. It appeared during the early Jurassic Period and went extinct during the early Cretaceous Period, making it one of the longest-lived shark genera in the fossil record…. Read More ›

Trinacromerum

Trinacromerum was a 12 foot long plesiosaur which lived within the Mowry Sea, the shallow sea that covered North America during the middle of the Cretaceous Period 95 million years ago. The holotype specimen was found in 1888 within the… Read More ›

Platypterygius

Platypterygius, meaning “flat fin”, was a genus of ichthyosaur which lived during the middle of the Cretaceous Period approximately 115-95 million years ago. It was one of the last ichthyosaurs to exist before the entire group went extinct. Traditionally treated… Read More ›

Cryptoclidus

Cryptoclidus was a 15 foot long plesiosaur which inhabited the prehistoric Tethys Sea, which once covered much of Europe, during the middle of the Jurassic Period 165-160 million years ago. Fossils of Cryptoclidus have been found within southern England and… Read More ›