Editing Megatherium (section)

== Taxonomy and evolution ==
''Megatherium'' is divided into 2 [[Subgenus|subgenera]], ''Megatherium'' and ''Pseudomegatherium.'' Taxonomy according to Pujos (2006) and De Iuliis ''et al'' (2009):<ref name="Pujos2006" /><ref>{{Cite journal |last1=De Iuliis |first1=Gerardo |last2=Pujos |first2=François |last3=Tito |first3=Giuseppe |date=2009-12-12 |title=Systematic and taxonomic revision of the Pleistocene ground sloth Megatherium (Pseudomegatherium) tarijense (Xenarthra: Megatheriidae) |journal=Journal of Vertebrate Paleontology |volume=29 |issue=4 |pages=1244–1251 |bibcode=2009JVPal..29.1244D |doi=10.1671/039.029.0426 |issn=0272-4634 |s2cid=84272333}}</ref>

* Subgenus ''Megatherium''
** †''M. altiplanicum'' {{small|Saint-André & de Iuliis 2001}}
** †''M. americanum'' {{small|Cuvier 1796}}
** ''†M. gallardoi'' <small>Ameghino & Kraglievich, 1921</small>
*Subgenus ''Pseudomegatherium'' {{small|Kraglievich 1931}}
** †''M. celendinense'' {{small|Pujos 2006}}
** †''M. medinae'' {{small|Philippi 1893}}
** †''M. sundti'' {{small|Philippi 1893}}
** †''M. tarijense'' {{small|Gervais & Ameghino, 1880}}
** †''M. urbinai'' {{small|Pujos & Salas 2004}}
''Megatherium gallardoi'' <small>Ameghino & Kraglievich, 1921</small> from the Pampas dating to the [[Pleistocene|Early]] to [[Middle Pleistocene]]<ref name=":9" /> has sometimes been regarded as a synonym of ''M. americanum''.<ref name=":15" /> The species ''Megatherium filholi'' <small>Moreno, 1888</small> also from the Pleistocene of the Pampas region, historically regarded to be a junior synonym of ''M. americanum'' representing juvenile individuals has been suggested to be valid by some recent authors.<ref name=":14">{{Cite journal |last1=Agnolin |first1=Federico L. |last2=Chimento |first2=Nicolás R. |last3=Brandoni |first3=Diego |last4=Boh |first4=Daniel |last5=Campo |first5=Denise H. |last6=Magnussen |first6=Mariano |last7=De Cianni |first7=Francisco |date=2018-09-01 |title=New Pleistocene remains of Megatherium filholi Moreno, 1888 (Mammalia, Xenarthra) from the Pampean Region: Implications for the diversity of Megatheriinae of the Quaternary of South America |journal=Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen |language=en |volume=289 |issue=3 |pages=339–348 |doi=10.1127/njgpa/2018/0777 |hdl=11336/80117 |issn=0077-7749 |s2cid=134660849}}</ref> ''Megatherium gaudryi'' <small>Moreno (1888)</small> from Argentina, of uncertain temporal provenance but possibly Pliocene in age, may also be valid.<ref name=":9">{{Cite journal |last1=Chimento |first1=Nicolás R. |last2=Agnolin |first2=Federico L. |last3=Brandoni |first3=Diego |last4=Boh |first4=Daniel |last5=Magnussen |first5=Mariano |last6=De Cianni |first6=Francisco |last7=Isla |first7=Federico |date=April 2021 |title=A new record of Megatherium (Folivora, Megatheriidae) in the late Pliocene of the Pampean region (Argentina) |url=https://linkinghub.elsevier.com/retrieve/pii/S0895981120304934 |journal=Journal of South American Earth Sciences |language=en |volume=107 |pages=102950 |doi=10.1016/j.jsames.2020.102950|bibcode=2021JSAES.10702950C }}</ref>

[[Mitochondrial DNA]] sequences obtained from ''M. americanum'' indicates that [[three-toed sloth]]s (''Bradypus'') are their closest living relatives. Phylogeny of sloths after Delsuc et al. 2019.<ref name=":8">{{Cite journal |last1=Delsuc |first1=Frédéric |last2=Kuch |first2=Melanie |last3=Gibb |first3=Gillian C. |last4=Karpinski |first4=Emil |last5=Hackenberger |first5=Dirk |last6=Szpak |first6=Paul |last7=Martínez |first7=Jorge G. |last8=Mead |first8=Jim I. |last9=McDonald |first9=H. Gregory |last10=MacPhee |first10=Ross D.E. |last11=Billet |first11=Guillaume |last12=Hautier |first12=Lionel |last13=Poinar |first13=Hendrik N. |date=June 2019 |title=Ancient Mitogenomes Reveal the Evolutionary History and Biogeography of Sloths |url=https://linkinghub.elsevier.com/retrieve/pii/S096098221930613X |journal=Current Biology |language=en |volume=29 |issue=12 |pages=2031–2042.e6 |doi=10.1016/j.cub.2019.05.043|pmid=31178321 |bibcode=2019CBio...29E2031D }}</ref>

{{clade
|label1=[[Folivora]] (sloths)
|1={{clade
|1={{extinct}}[[Megalocnidae|Caribbean sloths]]
|2={{clade
|label1=Mylodontoidea
|1={{clade
|1=[[Two-toed sloths]] ''(Choelopus)''
|2={{extinct}}[[Mylodontidae]] (''[[Mylodon]]'')
}}
|label2=Megatherioidea
|2={{clade
|1={{extinct}}[[Megatheriidae]] ('''''Megatherium''''')
|2={{clade
|1={{clade
|1={{extinct}}[[Megalonychidae]] (''[[Megalonyx]]'')
|2={{extinct}}[[Nothrotheriidae]] (''[[Nothrotheriops]]'')
}}
|2=[[Three-toed sloths]] (''Bradypus'')
}}}}}}}}}}[[Megatheriidae]] is suggested to have diverged from other sloth families during the [[Oligocene]], around 30 million years ago.<ref name=":8" /> The subfamily to which ''Megatherium'' belongs, [[Megatheriinae]], first appeared in the [[Middle Miocene]] in [[Patagonia]], at least 12 million years ago, represented by the genus ''[[Megathericulus]]''.<ref>{{Cite journal |last1=Brandoni |first1=Diego |last2=Carlini |first2=Alfredo A |last3=Anaya |first3=Federico |last4=Gans |first4=Phil |last5=Croft |first5=Darin A |date=September 2018 |title=New Remains of Megathericulus patagonicus Ameghino, 1904 (Xenarthra, Tardigrada) from the Serravallian (Middle Miocene) of Bolivia; Chronological and Biogeographical Implications |url=http://link.springer.com/10.1007/s10914-017-9384-y |journal=Journal of Mammalian Evolution |language=en |volume=25 |issue=3 |pages=327–337 |doi=10.1007/s10914-017-9384-y |issn=1064-7554}}</ref> The earliest known remains of the genus ''Megatherium'' are known from the [[Pliocene]], found in Bolivia (''M. altiplanicum'') and the Pampas (indeterminate species), dating to at least 3.6 million years ago.<ref name=":9" /><ref name=":3" /> ''M. altiplanicum'' is suggested to be more closely related to ''M. americanum'' than to species of ''Pseudomegatherium''. Phylogeny of Megatheriinae after Pujos, 2006:<ref name="Pujos2006" />
{{clade
|label1=[[Megatheriinae]]
|1={{clade
|1=''[[Plesiomegatherium]]''
|2=''[[Megathericulus]]''
|3={{clade
|1={{clade
|1=''[[Megatheriops]]''
|2=''[[Pyramiodontherium]] bergi''
|3=''Pyramiodontherium brevirostrum''}}
|2={{clade
|1=''[[Eremotherium]]''
|label2='''''Megatherium'''''
|2={{clade
|label1=''Megatherium'' (''Megatherium'')
|1={{clade
|1= ''Megatherium americanum''
|2= ''Megatherium altiplanicum''
}}
|label2=''Megatherium'' (''Pseudomegatherium'')
|2={{clade
|1=''Megatherium sundti''
|2={{clade
|1=''Megatherium urbinai''
|2={{clade
|1=''Megatherium celendinense''
|2={{clade
|1=''Megatherium medinae''
|2=''Megatherium tarijense''
}}}}}}}}}}}}}}}}}}''Megatherium americanum'' first appears in the fossil record during the second half of the [[Middle Pleistocene]], from around 400,000 years ago.<ref>{{Cite journal |last1=Prado |first1=José Luis |last2=Alberdi |first2=María Teresa |last3=Bellinzoni |first3=Jonathan |date=June 2021 |title=Pleistocene Mammals from Pampean Region (Argentina). Biostratigraphic, Biogeographic, and Environmental Implications |journal=Quaternary |language=en |volume=4 |issue=2 |pages=15 |doi=10.3390/quat4020015 |doi-access=free |issn=2571-550X}}</ref>