† Juramaia sinensis Luo et al., 2011

Metatheria + Eutheria represent an evolutionary novelty. Probably had an "ancestor" who lived on the ground. Similar to solenodon, with long nails, as Monotremata, Pholidota and Xenarthra. Dentition as in Juramaia.The rinarhium was like a marsupial, the tail was nude with scales, as well as the paws.
A mammal as Juramaia emerged between Marsupialia and Carnivora. There was molarization of the last premolars in marsupials. Sinodelphys preserved the last lower premolar not molarized. SEE HERE