Asiadelphia is an order of Cretaceous

Cretaceous

The Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...

 Metatherians. Different from the Ameridelphia

Ameridelphia

Ameridelphia is traditionally a superorder that includes all marsupials living in the Americas except for the Monito del Monte...

, they lacked a prominent distolateral process on the scaphoid, and possessed a more slender fibula. The masseteric fossa is deeper in this group than the true Marsupial

Marsupial

Marsupials are an infraclass of mammals, characterized by giving birth to relatively undeveloped young. Close to 70% of the 334 extant species occur in Australia, New Guinea, and nearby islands, with the remaining 100 found in the Americas, primarily in South America, but with thirteen in Central...

s.

Further reading

Zofia Kielan-Jaworowska, Richard L. Cifelli, and Zhe-Xi Luo, Mammals from the Age of Dinosaurs: Origins, Evolution, and Structure (New York: Columbia University Press, 2004), 15, 451-452.