Editing Litopterna (section)

{{Short description|Extinct order of hoofed mammals}}
{{Automatic taxobox
| fossil_range = {{Fossil range|Paleocene|Holocene}}
| image = Macrauchenia patachonica Skeletal (cropped).png
| image_caption = Skeleton of  ''[[Macrauchenia]]'' ([[Macraucheniidae]])
| image2 = Reports of the Princeton University Expeditions to Patagonia, 1896-1899. J. B. Hatcher in charge (1901) (14563211299).jpg
| image2_caption = Skeleton of ''[[Diadiaphorus]]'' ([[Proterotheriidae]])
| taxon = Litopterna
| authority = [[Florentino Ameghino|Ameghino]] 1889
| subdivision_ranks = Subgroups
| subdivision = *{{extinct}}[[Didolodontidae]]?
*{{extinct}}[[Notonychopidae]]
*{{extinct}}[[Protolipternidae]]
*{{extinct}}[[Sparnotheriodontidae]]
*{{extinct}}[[Indaleciidae]]
*{{extinct}}'''Lopholipterna'''
**{{extinct}}'''Proterotherioidea'''
***{{extinct}}[[Proterotheriidae]]
**{{extinct}}'''Macrauchenioidea'''
***{{extinct}}[[Adianthidae]]
***{{extinct}}[[Macraucheniidae]]
}}

'''Litopterna''' (from {{langx|grc|λῑτή πτέρνα}} "smooth heel") is an [[extinction|extinct]] order of [[South American native ungulates]] that lived from the [[Paleocene]] to the [[Pleistocene]]-[[Holocene]] around 62.5 million to 12,000 years ago (or possibly as late as 3,500 years ago), and were also present in Antarctica during the [[Eocene]]. They represent the second most diverse group of South American ungulates after [[Notoungulata]].<ref name="Croft-2020">{{Cite journal |last1=Croft |first1=Darin A. |last2=Gelfo |first2=Javier N. |last3=López |first3=Guillermo M. |date=2020-05-30 |title=Splendid Innovation: The Extinct South American Native Ungulates |url=https://www.annualreviews.org/doi/10.1146/annurev-earth-072619-060126 |journal=Annual Review of Earth and Planetary Sciences |language=en |volume=48 |issue=1 |pages=259–290 |doi=10.1146/annurev-earth-072619-060126 |bibcode=2020AREPS..48..259C |s2cid=213737574 |issn=0084-6597|url-access=subscription }}</ref> It is divided into nine families, with [[Proterotheriidae]] and [[Macraucheniidae]] being the most diverse and last surviving families.<ref name="Carrillo-2023">{{Cite journal |last1=Carrillo |first1=Juan D. |last2=Suarez |first2=Catalina |last3=Benites-Palomino |first3=Aldo Marcelo |last4=Vanegas |first4=Andrés |last5=Link |first5=Andrés |last6=Rincón |first6=Aldo F. |last7=Luque |first7=Javier |last8=Cooke |first8=Siobhán B. |last9=Tallman |first9=Melissa |last10=Billet |first10=Guillaume |date=2023-08-31 |title=New remains of Neotropical bunodont litopterns and the systematics of Megadolodinae (Mammalia: Litopterna) |journal=Geodiversitas |volume=45 |issue=15 |doi=10.5252/geodiversitas2023v45a15 |s2cid=261638835 |issn=1280-9659}}</ref>