Oldfieldthomasiidae Temporal range: Late Paleocene-Late Eocene ~58.7–33.9 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	†Notoungulata
Suborder:	†Typotheria
Family:	†Oldfieldthomasiidae Simpson, 1945
Genera
†Allalmeia †Brachystephanus †Camargomendesia †Colbertia †Dolichostylodon †Itaboraitherium †Kibenikhoria †Maxschlosseria †Oldfieldthomasia †Paginula †Suniodon †Tsamnichoria †Ultrapithecus †Xenostephanus
Synonyms
Acoelodidae Ameghino 1901

Oldfieldthomasiidae is an extinct family of notoungulate mammals known from the Late Paleocene to Late Eocene of South America.^[1] The family was classified by George Gaylord Simpson in 1945 and a synonym is Acoelodidae, defined by Florentino Ameghino in 1901.^[2]

Etymology

The family is named after British zoologist Oldfield Thomas.

Fossils

Fossils of the family Oldfieldthomasiidae have been found in southern South America, in Argentina, Bolivia, Brazil and Chile.^[2]