First temnodontosaurid (Ichthyosauria, Parvipelvia) from the Lower Jurassic of the Atacama Desert, northern Chile

摘要

We describe fragmentary ichthyosaur skull remains of a single individual recovered from Lower Jurassic marine strata in northern Chile. The preserved teeth display distinctive features such as a very long, robust and coarsely infolded roots; as well as low, labio-lingually compressed, large triangular crowns with carinae. Dental features are consistent with those of the genus Temnodontosaurus, previously known in the Lower Jurassic of Europe. This find represent the first record of a temnodontosaurid ichthyosaur in the southern hemisphere, reinforcing a pattern of faunal interchange between the northern Tethys and southern Panthalassa, prior to the separation of Laurasia and Gondwana, and before the full establishment of the Caribbean Seway.