Ichthyotitan

Ichthyotitan Temporal range: Late Triassic (Rhaetian), 205–202 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Holotype (A, C) and referred (B, D) specimens of Ichthyotitan
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	†Ichthyosauria
Family:	†Shastasauridae (?)
Genus:	†Ichthyotitan Lomax et al., 2024
Species:	†I. severnensis
Binomial name
†Ichthyotitan severnensis Lomax et al., 2024

Ichthyotitan (/ˌɪkθiəˈtaɪtən/ IK-thee-ə-TY-tən) is an extinct genus of giant ichthyosaur from the Late Triassic (Rhaetian), known from the Westbury Mudstone Formation in Somerset, England. It is believed to be a shastasaurid, extending the family's range by 13 million years up to the latest Triassic. The discovery of Ichthyotitan has been considered evidence that shastasaurids were still thriving until their disappearance in the Triassic–Jurassic extinction event.

The genus contains a single species, I. severnensis. It is known from two fragmentary surangular bones of the lower jaw, discovered in separate places in 2016 and 2020. Other specimens throughout Western Europe have been linked to the species based on similar osteological features, although their affiliation is uncertain. Estimates scaling up the bones from other ichthyosaur species put Ichthyotitan's body length at nearly 25 metres (82 ft), which would make it the largest marine reptile currently known.