Didelphodon (meaning "two womb tooth) is a genus of stagodont marsupial from the Late Cretaceous of North America. It was a very large mammal compared to most other mammal species in the Mesozoic era. Despite its size, it was a powerful carnivore with extremely powerful jaws. It was a primarily aquatic predator similar to an otter, where it used its strong jaws to crush mollusks. However, it also had an omnivorous diet where it fed on mollusks, dinosaur eggs, lizards, and plants.
In The Land Before Time
A pair of Didelphodon briefly appear in the the opening narration of The Land Before Time V: The Mysterious Island, where they are seen interacting in front of a Corythosaurus before being scared off by an approaching rival Corythosaurus in a fight for territory, which is later followed by an attacking Tyrannosaurus.