Triassic British Columbia

Thalattosaurus (pronounced: , from and ) is an extinct genus of marine reptile in the family Thalattosauroidea. Known exclusively from the Triassic period, it was a long shellfish-eating diapsid with paddle-like limbs and a down-turned rostrum. Fossils were recovered in the Lower and Middle Triassic Sulphur Mountain Formation of British Columbia as well as the Upper Triassic Hosselkus Limestone of California. It has gained notoriety as a result of studies on general diapsid phylogeny.

Hudsonelpidia is an extinct genus of small parvipelvian ichthyosaur known from British Columbia of Canada.