Typotheria is a

suborder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

of the

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

ian order Notoungulata and includes five families:

Archaeopithecidae Archaeopithecidae is an extinct family comprising two genera of notoungulate mammals, '' Teratopithecus'' and '' Archaeopithecus'', both known from the Eocene of Argentina.Campanorcidae ''Campanorco'' is an extinct genus of notoungulate mammal from the Middle Eocene Lumbrera Formation, Argentina, South America and the only member of the family Family (from la, familia) is a group of people related either by consanguini ...

Interatheriidae Interatheriidae is an extinct family of notoungulate mammals from South America. Interatheriids are known from the Middle Eocene (Mustersan) to the Early Pliocene (Montehermosan).McKenna & Bell, 1997Linares, 2004 These animals were principally sm ...

Mesotheriidae Mesotheriidae ("Middle Beasts") is an extinct family of notoungulate mammals known from the Oligocene through the Pleistocene of South America. Mesotheriids were small to medium-sized herbivorous mammals adapted for digging. Characteristics Meso ...

, and

Oldfieldthomasiidae Oldfieldthomasiidae is an extinct family of notoungulate mammals known from the Late Paleocene to Late Eocene of South America. The family was classified by George Gaylord Simpson in 1945 and a synonym is Acoelodidae, defined by Florentino Ameghi ...

. CifelliCifelli, Richard L. 1993. The phylogeny of the native South American ungulates. pp. 195-216 ''in'' F. S. Szalay, M. J. Novacek and M. C. McKenna (''eds.'') ''Mammal Phylogeny, Volume 2, Placentals''. Springer-Verlag, New York. indicated that Typotheria would be paraphyletic if it excluded members of the suborder

Hegetotheria Typotheria is a suborder of the extinct mammalian order Notoungulata and includes five families: Archaeopithecidae, Campanorcidae, Interatheriidae, Mesotheriidae, and Oldfieldthomasiidae. CifelliCifelli, Richard L. 1993. The phylogeny of the nati ...

and he advocated inclusion of the hegetothere families

Archaeohyracidae Archaeohyracidae is an extinct family of notoungulate mammals known from the Paleocene through the Oligocene of South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a ...

and

Hegetotheriidae Hegetotheriidae is an extinct family of notoungulate mammals known from the Oligocene through the Pliocene of South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a r ...

in Typotheria.

References

Prehistoric animal suborders Mammal suborders {{paleo-mammal-stub