views updated

Protoungulata (infraclass Eutheria, cohort Ferungulata) A superorder that comprises the orders Condylarthra, Notoungulata, Litopterna, Astrapotheria, and Tubulidentata. The superorder includes the earliest known ungulates from their appearance during the late Cretaceous, when they departed from an insectivorous diet and began to eat plant material, until the end of the Palaeocene by which time their radiation permits them to be grouped in distinct orders from some of which later ungulates are descended. The Tubulidentata, known to have lived in the Miocene and possibly in the Eocene, are animals apparently similar to condylarths and so are included in the superorder, but otherwise they are isolated zoologically and their affinities are obscure.