''Maastrichtidelphys'' is a Late

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

genus of

metatherian Metatheria is a mammalian clade that includes all mammals more closely related to marsupials than to placentals. First proposed by Thomas Henry Huxley in 1880, it is a more inclusive group than the marsupials; it contains all marsupials as well ...

(marsupial lineage) mammal from the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

in Europe.Martin, J.E., Case, J.A., Jagt, J.W., Schulp, A.S. and Mulder, E.W., 2005
A new European marsupial indicates a Late Cretaceous high-latitude transatlantic dispersal route
''Journal of Mammalian Evolution'', 12(3-4), pp.495-511. The genus contains a single species, ''M. meurismeti''. It is known from an extremely small right upper molar, and analysis of it suggests that ''Maastrichtidelphys'' is most closely related to the North American herpetotheriid marsupial, '' Nortedelphys'', which is

Lancian The Lancian was a North American faunal stage of the Late Cretaceous. It was the final stage of the Cretaceous period in North America, lasting from approximately 70.6 to 66 million years ago. Geology Terrestrial sedimentary strata from the Judit ...

in age. ''Maastrichtidelphys'' belongs to a group of mammals with their origins in North America, the

Herpetotheriidae Herpetotheriidae is an extinct family of metatherians, closely related to marsupials. Species of this family are generally reconstructed as terrestrial, and are considered morphologically similar to modern opossums. Fossils of herpetotheriids com ...

. The presence of ''Maastrichtidelphys'' in Europe in the Late Cretaceous shows there was a high-latitude North Atlantic dispersal route between North America and Europe for marsupials, which suggests they spread across Europe at least 10 million years earlier than previously thought.

References

Prehistoric metatherians Prehistoric mammal genera Prehistoric monotypic mammal genera Fossil taxa described in 2005 {{cretaceous-mammal-stub