dolphin-like reptile lived during the Triassic and Jurassic periods. Anatomical features demonstrate that it was a visually-oriented predator; it had huge, sensitive eyes, protected by bony shields. Coprolites of Ichthyosaurus reveal that its diet consisted of fish and squid. Ichthyosaurus was smaller than most of its relatives, with individuals measuring up to 11 ft (3.3 m) in length.
These marine reptiles grew to be up to 49 ft (15 m) long. The group thus contained some of the largest marine apex predators in the fossil record, roughly equalling the longest ichthyosaurs, mosasaurids, sharks and toothed whales in size. They lived in the Triassic period and became especially common during the Jurassic period, thriving until their disappearance due to the Cretaceous–Paleogene extinction event at the end of the Cretaceous Period.
Warning - Creatures like these are a good reason not to go swimming while on your vacation in the Jurassic.
Did you know? - Plesiosaurs were among the first fossil reptiles discovered.
Some marine crocodyliforms existed during the Jurassic, namely of the families Teleosauridae and Metriorhynchidae.
The teleosaurids were marine crocodyliforms similar to the modern gharial that lived from the Early Jurassic to the Early Cretaceous. They had long snouts, indicative of their piscivore diet and were the closest relatives to the Metriorhynchidae, the Mesozoic crocodilians that returned to the sea and evolved paddle-like forelimbs and a shark-like tail.
Metriorhynchids are fully aquatic crocodyliforms. Their forelimbs were small and paddle-like, and unlike living crocodilians, they lost their armour scutes. Their body shape maximised swimming efficiency, as they did have a shark-like tail fluke.