Ichthyotitan severnensis

Ichthyotitan is the only shastasaurid and giant ichthyosaur to be known from the Rhaetian, found in the fossil record 13 million years after their relatives. The lineage is believed to have gone extinct immediately after in the Triassic–Jurassic extinction event, with later ichthyosaurs never reaching similar sizes until their extinction in the early Late Cretaceous.