They are distinguished by the presence of epipubic bones and the lack of a corpus callosum, as well as by the distinctive pouch.
These are thought to have evolved in North America, where the genus Thlaedon is the largest member of its class from the Cretaceous. South American representatives include the extinct carnivores Borhyaena and the sabre-toothed Thylacosmilus as well as the rat-like Caenolestes. They are distinguished by the presence of epipubic bones and the lack of a corpus callosum, as well as by the distinctive pouch. FTP, name this mammalian superorder with living representatives concentrated in Australia.
These are thought to have evolved in North America, where the genus Thlaedon is the largest member of its class from the Cretaceous.
marsupials