Paleontology in Mongolia

Amtosaurus () is a genus of ornithischian dinosaur based on a fragmentary skull collected from the Late Cretaceous (Cenomanian to Turonian) Bayanshiree Formation of Mongolia and originally believed to represent an ankylosaurid. Hadrosaurid affinities have also been suggested. However, according to Parish and Barrett, this specimen is too fragmentary to be reliably classified beyond an indeterminate ornithischian. A second species assigned to the genus, A. archibaldi, has become the basis of a valid ankylosaurid taxon, Bissektipelta.

Tchoiria () is a genus of neochoristoderan reptile from the Early Cretaceous of Mongolia. The name Tchoiria comes from the city of Choir which is nearby to where the holotype was found. Tchoiria is thought to have a similar diet to another neochoristoderan reptile, Champsosaurus, due to morphology of the skull. It would hunt in freshwater environments, like the living gharials, where it would prey on many different types of fish and turtles.

geological formation in Mongolia