Megatheriinae is a subfamily of the

Megatheriidae Megatheriidae is a family of extinct ground sloths that lived from approximately 23 mya—11,000 years ago. Megatheriids appeared during the Late Oligocene (Deseadan in the SALMA classification), some 29 million years ago, in South America ...

, an extinct family of ground sloths that lived from the Middle Miocene to the Early Holocene.

Classification

Within the Megatheriidae there are two (possibly three) subfamilies; the Megatheriinae and the Planopsinae. The phylogenetically older group is represented by the Planopsinae from the Lower and Middle Miocene. These still possessed a caniniform anterior tooth, which was separated from the posterior molar-like teeth by a small diastema . The more derived Megatheriinae, which are known from the Middle Miocene to the Early Holocene, on the other hand, had fully homodontic molars in a closed row. Originally, the subfamilies of the Nothrotheriinae and the Schismotheriinae were also placed in the Megatheriidae. Based on skull studies, the Nothrotheriidae, in which, among other genera, ''

Nothrotherium ''Nothrotherium'' is an extinct genus of medium-sized ground sloth from South America (Bolivia, Brazil and the Ware Formation, La Guajira, Colombia).Amson et al., 2016, p.12 It differs from ''Nothrotheriops'' in smaller size and differences in sk ...

'', ''

Nothrotheriops ''Nothrotheriops'' is a genus of Pleistocene ground sloth found in North America, from what is now central Mexico to the southern United States. This genus of bear-sized xenarthran was related to the much larger, and far more famous '' Megatheriu ...

,'' and the semiaquatic ''

Thalassocnus ''Thalassocnus'' is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—''T. antiquus'', ''T. natans'', ''T. lit ...

'' are placed, are regarded as a separate family, which forms the sister group of the Megatheriidae.

References

{{Taxonbar, from=Q20072315 Prehistoric sloths Prehistoric animal subfamilies Burdigalian first appearances Holocene extinctions Miocene xenarthrans Pliocene xenarthrans Pleistocene xenarthrans