Eutheria

Placentalia

Eutheria. Eutheria (/juːˈθɪəriə/; from Greek ευ-, eu- "true/good" and θηρίον, thērion "beast" hence "true beasts") is one of two mammalian clades with extant members that diverged in the Early Cretaceous or perhaps the Late Jurassic.

The other is the Metatheria, which includes marsupials, most of whom accommodate their neonates in pouches. Except for the Virginia opossum, which is a metatherian, all mammals indigenous to Europe, Africa, Asia, and North America north of Mexico are eutherians. Extant eutherians, their last common ancestor, and all extinct descendants of that ancestor are placentals, in the group Placentalia.