X-Nico

3 unusual facts about UA 8699


UA 8699

UA 8699 lacks a cingulid (ridge) resembling a shelf on the lingual (inner) side, indicating that is not a member of Australosphenida (the proposed clade uniting monotremes and some ancient Gondwanan mammals, including the Jurassic Madagascan Ambondro); thus, it can be identified as representing Boreosphenida, which includes marsupials, placentals, and their extinct relatives.

Averianov, Archibald, and Martin instead placed UA 8699 in the context of faunal similarity and exchange between the late Cretaceous faunas of Europe and Africa, noting the presence of similar animals, such as snakes (Medtsoia) and sauropods (Lirainosaurus and Repetosaurus), in the Cretaceous faunas of Madagascar and the Spanish locality Laño.

These include the gondwanathere Lavanify, an indeterminate multituberculate, and a few other indeterminate teeth, as well as a nearly complete skeleton representing an otherwise unknown mammalian lineage.


Similar


see also