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{{Italic title}}{{Taxobox
| name = ''Paramylodon''
| fossil_range = late [[Pliocene]] to [[Pleistocene]]
| image = San Diego Paramylodon.jpg
| image_width = 250px
| image_caption = Skeleton in San Diego
| regnum = [[Animal]]ia
| phylum = [[Chordata]]
| classis = [[Mammalia]]
| superordo = [[Xenarthra]]
| ordo = [[Pilosa]]
| familia = †[[Mylodontidae]]
| subfamilia = †[[Lestodontinae]]
| tribus = {{extinct}}[[Glossotheriini]]
| genus = [[extinction|†]]'''''Paramylodon'''''
| genus_authority = [[Barnum Brown|Brown]], 1903
| species = †''P. harlani''  (Owen), 1840
}}

'''''Paramylodon''''' is an extinct genus of [[ground sloth]] of the family [[Mylodontidae]] endemic to [[North America]] during the [[Pliocene]] through [[Pleistocene]] epochs, living from around ~4.9 [[Mya (unit)|Mya]]—11,000 years ago (approximately {{Mya|4.9-0.011|million years}}).
==Description==
[[Image:La Brea Tar Pits.jpg|thumb|left|La Brea Tar Pits fauna including ''Paramylodon'' by [[Charles R. Knight]]]]
''Paramylodon'' measured about 3 m (9.8 ft) in height and weighted as much as 1089 kg.<ref>http://library.sandiegozoo.org/factsheets/_extinct/sloth_extinct/extinct_sloth.htm</ref> It is known from North America deposits, including in [[Mexico]] and the United States and as far south as [[Guatemala]], and often mistaken as ''[[Glossotherium]]''. Currently there is just one recognized species, ''P. harlani'', (Owen) 1840, which is commonly referred to as Harlan's ground sloth in honor of American paleontologist Dr. [[Richard Harlan]] who first discovered and described a lower jaw in 1835.  ''Paramylodon'' exhibits the interesting characteristic of having had [[dermal ossicle]]s, small bones embedded in the skin, presumably adding a degree of protection to the animal. This characteristic is also shared by the South American ''[[Mylodon]]''.

==Taxonomic history==
The genus was created by [[Barnum Brown]] in 1903 with the species ''P. nebrascensis''.  The skull showed a number of characteristics similar to that of ''Mylodon harlani'', which was also known from North America, but differed in the number of teeth present in the maxilla.  ''Paramylodon'' had four teeth in the upper dentition, similar to that of ''Grypotherium darwini'' (=''Mylodon darwini''), but the then recognized genus of ''Mylodon'' possessed five upper teeth.  ''P. nebrascensis'' was later considered to be a junior synonym of ''M. harlani'' by Stock (1925) given the large number of specimens from the [[La Brea Tar Pits]] that showed the presence of the upper caniniform to be variably lost in some specimens and retained in others.  Thus the typical dental formula for the species of ''harlani'' is <math>5/4</math>.  Work by Kraglievich (1928) sorted through the long standing historical confusion concerning the taxonomic validity of ''Mylodon'' and ''Glossotherium'', and determined what the type species of each genus was.  An additional result was to recognize ''Paramylodon'' as generically different from ''Mylodon'' of South America and ''P. harlani'' was used as the species name as it had seniority over ''P. nebrascensis''.
[[File:Glossotherium harlani p1350719.jpg|thumb|upright|Skeleton from the La Brea Tar Pits]] 
Until recently, ''Paramylodon'' was also viewed as a subspecies of ''Glossotherium'' and a number of institutions listed their specimens as ''Glossotherium harlani'' in part to work by Robertson (1976).  ''Paramylodon'' is generically distinct from the South American genus of ''Glossotherium'' (see McAfee, 2007), although some question remains regarding the relationship of the late Blancan specimens that have been tentatively assigned as ''"Glossotherium" chapadmalense'' due to their seeming similarity to the South American species of the same name.

==Fossil distribution==
Sites and specimen ages (not complete):
*El Golfo de Santa Clara Site, [[Sonora, Mexico]] ~4.9—1.8 Mya.
*Tri-Britton Site, [[Hendry County, Florida]] ~2.1 Mya.—700,000 years ago.
*Turin Pit Site (or Elliott Pit) [[Monona County, Iowa]] ~1.8—300,000 years ago.
*Port Kennedy Cave Site, [[Montgomery County, Pennsylvania]] ~1.8 Mya.—300,000 years ago.
*Fairmead Landfill Site, [[Madera County, California]] ~1.8 Mya.—300,000 years ago.
*Rio de la Pasion Site, [[Petén (department)|Petén]], [[Guatemala]] ~100,000—11,000 years ago.
*[[Tualatin, Oregon|Tualatin]], [[Oregon]]-15,000 to 10,000 years ago.
*Medicine Hat Unit V Site, [[Alberta, Canada]] ~1.8 Ma—11,000 years ago.<ref>[http://paleodb.org/cgi-bin/bridge.pl?action=basicCollectionSearch&collection_list=20417 Paleobiology database: Medicine Hat Unit V collection].</ref>

===Notable discoveries===
[[File:Paramylodon_at_Field_Museum.jpg|thumb|right|''Paramylodon'' from Rancho La Brea on display at the Field Museum in Chicago]]
Recently a ''Paramylodon harlani'' specimen was identified from the Tarkio Valley site in Iowa association with ''[[Megalonyx]] jeffersoni''.  This is the first occurrence of ''Paramylodon'' in Iowa, and probably the first time these species have been found in close association.<ref>"Fourth sloth discovered", comment on ''The Tarkio Valley Sloth Project'', http://slothcentral.com/archives/529/comment-page-1#comment-1787</ref> These two species have since been uncovered at the Fairmead Landfill Site and Irvington Site in California.

On December 3, 2009, the Press-Enterprise newspaper reported a specimen skull to have been recovered in San Timoteo Canyon.[http://www.pe.com/localnews/inland/stories/PE_News_Local_S_sloth03.2dc60eb.html]

==References==
{{Reflist}}
* {{aut|Brown, B.}} (1903): A new genus of ground sloth from the Pleistocene of Nebraska. ''Bulletin of the American Museum of Natural History'', 19:569-583.
* {{aut|Harlan, R.}} (1935): Medical and physical researches. pp.&nbsp;271–275; 314-336.
* {{aut|Kraglievich, L.}} (1928): "''Mylodon Darwin''" Owen, es la especie genotipo de "''Mylodon''" Ow. ''Revista de la Sociedad Argentina de Ciencias Naturales, Physis'': 9(33): 169-185.
* {{aut|McAfee, R.K.}} (2007): ''Reassessing the Taxonomy and Affinities of the Mylodontinae Sloths, Glossotherium and Paramylodon (Mammalia: Xenarthra: Tardigrada)''. Ph.D. Dissertation, Northern Illinois University. DeKalb, IL: 177pp.
* {{aut|Robertson, J.}} (1976): Latest Pleistocene mammals from Haile XV A, Alachua County, Florida. ''Bulletin of the Florida State Museum'', 20(3):111-186.
* {{aut|Stock, C.}} (1925): ''Cenozoic gravigrade edentates of western North America with special reference to the Pleistocene Megalonychinae and Mylodontidae of Rancho La Brea''.  Carnegie Institute of Washington, 331: 1-206.

==External links==
*[http://www.sloth-world.org Sloth World: an on-line bibliography]
*[http://www.tarpits.org/education/guide/flora/sloth.html Page Museum: info on ground sloths from the La Brea tar pits]

{{Portal|Palaeontology}}

[[Category:Prehistoric sloths]]
[[Category:Pleistocene xenarthrans]]
[[Category:Prehistoric animals of North America]]
[[Category:Megafauna of North America]]