''Brucemacfaddenia'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of interatheriine

notoungulate Notoungulata is an extinct order of ungulates that inhabited South America from the early Paleocene to the end of the Pleistocene, living from approximately 61 million to 11,000 years ago. Notoungulates were morphologically diverse, with forms re ...

s that lived during the Late

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

in what is now

Bolivia Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, w ...

. Fossils of this genus have been found in the

Salla Formation Salla, known as Kuolajärvi until 1936, is a municipality of Finland, located in Lapland. The municipality has a population of () and covers an area of of which is water. The population density is . The nearby settlement of Sallatunturi is ...

of Bolivia.

Etymology

The genus name, ''Brucemacfaddenia'', refers to Bruce MacFadden, known for his significant contributions of

Cenozoic The Cenozoic Era ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterized by the dominance of mammals, insects, birds and angiosperms (flowering plants). It is the latest of three g ...

mammal evolution in Bolivia. paleontology. The specific name, ''boliviensis'', refers to Bolivia, the country where it was found.

Description

''Brucemacfaddenia'' was a small-sized interatheriid. The derived features of ''Brucemacfaddenia'' that set it apart from other basal interatheriines such as ''

Proargyrohyrax ''Proargyrohyrax'' is an extinct genus of Interatheriinae, interatheriine Notoungulata, notoungulates that lived from the Early to Middle Oligocene in what is now Argentina. Fossils of this genus have been found in the Sarmiento Formation of Argen ...

'' and '' Santiagorothia'', by having hypselodont

cheek teeth Cheek teeth or postcanines comprise the molar and premolar teeth in mammals. Cheek teeth are multicuspidate (having many folds or tubercles). Mammals have multicuspidate molars (three in placentals, four in marsupials, in each jaw quadrant) and ...

an completely persistent lingual sulcus on the upper

molars The molars or molar teeth are large, flat tooth, teeth at the back of the mouth. They are more developed in mammal, mammals. They are used primarily to comminution, grind food during mastication, chewing. The name ''molar'' derives from Latin, '' ...

. Its

deciduous In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...

upper detention had thin enamel.

Taxonomy

''Brucemacfaddenia'' was first described in 2008 based on remains found in the

, in the La Paz Department, Bolivia, dating to the Late Oligocene, around 29 to 23 mya. It was described alongside another interatheriid, '' Federicoanaya sallaensis''. It is a basal member of the Interatheriidae family, more specifically within the subfamily

Interatheriinae Interatheriinae is an extinct subfamily of interatheriids that consisted of notoungulates dating from the Early Eocene (Casamayoran SALMA) to the Early Pliocene (Montehermosan SALMA). The subfamily includes the genera '' Archaeophylus'', '' Argy ...

. The following cladogram of the

is based on Vera ''et al.'' 2017, showing the position of ''Brucemacfaddenia''.

References

{{Taxonbar, from=Q115315665 Typotheres Prehistoric placental genera Oligocene mammals of South America Paleogene Bolivia Fossils of Bolivia Deseadan Fossil taxa described in 2008