''Neonematherium'' is an extinct genus of scelidotheriid

ground sloth Ground sloths are a diverse group of extinct sloths in the mammalian superorder Xenarthra. They varied widely in size with the largest, belonging to genera '' Lestodon'', ''Eremotherium'' and ''Megatherium'', being around the size of elephants. ...

s that lived in

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

, and

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

during the Early to Late Miocene. Fossils have been found in the Honda Group of Colombia, and the

Río Frías Formation Río Frías Formation () is a Miocene, Middle Miocene geologic formation made up sedimentary rock located in Aysén Region, western Patagonia. The formation crops out along the upper course of Cisnes River ().Marshall & Salinas, 1990 Marsupial fos ...

of Chile.

Taxonomy

''Neonematherium'' is a member of the Scelidotheriidae, a family of ground sloths known from the

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 ...

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

, and the

Early Holocene In the geologic time scale, the Greenlandian is the earliest age or lowest stage of the Holocene Epoch or Series, part of the Quaternary. Beginning in 11,650 BP (9701 BCE or 300 HE) and ending with the 8.2-kiloyear event (c. 8200–8300 B ...

epochs and are characterized by an elongated snout. Scelidotheres themselves part are usually placed as a subfamily of the

Mylodontidae Mylodontidae is a family of extinct South American and North American ground sloths within the suborder Folivora of order Pilosa, living from around 23 million years ago (Mya) to 11,000 years ago. This family is most closely related to another fa ...

, although they are sometimes considered a separate family,

Scelidotheriidae Scelidotheriidae is a family of extinct ground sloths within the order Pilosa, suborder Folivora and superfamily Mylodontoidea, related to the other extinct mylodontoid family, Mylodontidae, as well as to the living two-toed sloth family Choloepo ...

. Below is a phylogenetic tree of the

, based on the work of Nieto ''et al''. 2021, showing the position of ''Neonematherium''.

References

{{Taxonbar, from=Q113876473 Prehistoric sloths Prehistoric placental genera Burdigalian first appearances Langhian extinctions Miocene xenarthrans Miocene mammals of South America Friasian Colloncuran Laventan Mayoan Chasicoan Neogene Argentina Fossils of Argentina Neogene Chile Fossils of Chile Neogene Colombia Fossils of Colombia Honda Group, Colombia Fossil taxa described in 1904 Taxa named by Florentino Ameghino