The Virginia Opossum ( Didelphis virginiana ) , sometimes called a possum , is a marsupial . There are lots of marsupials in Australia , but the Virginia Opossum is the only North American marsupial . The Virginia Opossum ( Didelphis virginiana ) , commonly known as the North American Opossum or Tlacuache in Mexico , is the only marsupial found in North America north of Mexico .