Opossums are the largest order of marsupials in the Western Hemisphere, the Didelphimorphia.
Temporal range: Upper Cretaceous – Recent
|Virginia Opossum Didelphis virginiana|
The Virginia opossum was the first animal to be named an opossum: the word comes from the Algonquian language, and means "white beast". It was one of the few South American marsupials to establish itself permanently in North America after the Great American Interchange, and the only one to survive there today.