Abstract

Bayshinoryctes shuvalovi gen. et sp. nov. is based on a fragmentary skull including right maxilla associated with right and left dentaries with partially preserved dentition from the Upper Cretaceous (Turonian–Santonian) Bayinshire Formation at Bayshin Tsav locality in Gobi Desert, Mongolia. Undated Bayesian analyses of two different data matrices recover the new taxon as a stem placental mammal within the clade containing also Maelestes from the Upper Cretaceous (Campanian) of Mongolia and Batodon from the Upper Cretaceous (Maastrichtian) of North America. Bayshinoryctes gen. nov. differs from Maelestes by a few dental characters, including three-rooted P4, double-rooted p3, and p5 with metaconid swelling.