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Megalonyx jeffersonii (Jefferson's ground sloth)

Mammalia - Megalonychidae

Taxonomy
Megatherium jeffersonii was named by Desmarest (1822).

It was misspelled as Megalonyx jeffersoni by Leidy (1873) and Olson (1940); it was recombined as Megalonyx jeffersonii by Harlan (1825), Leidy (1855), Hay (1902), Lundelius (1972), Kurten and Anderson (1980), Thurmond and Jones (1981), Forster and Spamer (1986) and McDonald and Naples (2007).

Sister species lacking formal opinion data

View classification of included taxa

Synonyms
Synonymy list
YearName and author
1822Megatherium jeffersonii Desmarest
1825Megalonyx jeffersonii Harlan
1831Megalonyx laqueatus Harlan
1855Ereptodon priscus Leidy
1855Megalonyx dissimilis Leidy
1855Megalonyx jeffersonii Leidy
1873Megalonyx jeffersoni Leidy p. 229
1899Megalonyx priscus Cope
1902Megalonyx dissimilis Hay p. 577
1902Megalonyx jeffersonii Hay p. 577
1902Ereptodon priscus Hay p. 578
1905Megalonyx sierrensis Sinclair
1913Megalonyx californicus Stock
1938Megalonyx milleri Lyon
1940Megalonyx jeffersoni Olson p. 45
1940Megalonyx hogani Stovall
1950Megalonyx brachycephalus Stovall and McAnulty
1966Megalonyx brachycephalus Slaughter p. 80
1972Megalonyx jeffersonii Lundelius, Jr.
1980Megalonyx jeffersonii Kurten and Anderson p. 137
1981Megalonyx jeffersonii Thurmond and Jones p. 178
1986Megalonyx jeffersonii Forster and Spamer p. 183
2007Megalonyx jeffersonii McDonald and Naples p. 154

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RankNameAuthor
kingdomAnimalia()
Triploblastica
Nephrozoa
Deuterostomia
phylumChordataHaeckel 1847
subphylumVertebrata
superclassGnathostomata
Osteichthyes()
Sarcopterygii
subclassDipnotetrapodomorpha(Nelson 2006)
subclassTetrapodomorpha()
Tetrapoda()
Reptiliomorpha
Anthracosauria
Batrachosauria()
Cotylosauria()
Amniota
Synapsida()
RankNameAuthor
Therapsida()
infraorderCynodontia()
Epicynodontia
infraorderEucynodontia
Probainognathia
Mammaliamorpha
Mammaliaformes
classMammalia
subclassTribosphenida()
infraclassEutheria()
Placentalia
Americatheria
Xenarthra()
infraorderPilosaFlower 1883
familyMegalonychidaeGervais 1855
genusMegalonyxHarlan 1825
speciesjeffersonii(Desmarest 1822)

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

Diagnosis
No diagnoses are available
Measurements
No measurements are available
Composition: phosphaticsubp
Environment: terrestrialsubc
Locomotion: actively mobilec
Life habit: ground dwellingf
Diet: herbivoref
Created: 2005-06-08 10:11:09
Modified: 2005-08-22 18:30:05
Source: f = family, subc = subclass, c = class, subp = subphylum
References: Nowak 1991, Carroll 1988, Hendy et al. 2009, Ji et al. 2002

Age range: base of the Irvingtonian to the top of the Rancholabrean or 1.80000 to 0.01200 Ma

Collections (36 total)


Time interval Ma Country or state Original ID and collection number
Early/Lower Pleistocene2.588 - 0.781USA (Arizona) Megalonyx jeffersonii (85145)
Pleistocene2.588 - 0.0117USA (Illinois) Megalonyx jeffersonii (87059)
Pleistocene2.588 - 0.0117USA (Mississippi) Megalonyx jeffersoni (161954)
Pleistocene2.588 - 0.0117USA (West Virginia) Megalonyx jeffersonii (108095)
Pleistocene2.588 - 0.0117USA (South Carolina) Megalonyx jeffersoni (152904) Megalonyx jeffersonii (65405)
Irvingtonian1.8 - 0.3USA (Montana) Megalonyx jeffersonii (20310)
Irvingtonian1.8 - 0.3USA (Oklahoma) Megalonyx jeffersonii (20382)
Irvingtonian1.8 - 0.3USA (Iowa) Megalonyx jeffersonii (20556)
Irvingtonian1.8 - 0.3USA (Alabama) Megalonyx jeffersonii (20281)
Irvingtonian1.8 - 0.3USA (South Carolina) Megalonyx jeffersonii (79919)
Middle Pleistocene0.781 - 0.126USA (South Carolina) Megalonyx jeffersonii (79767 79768)
Middle Pleistocene0.781 - 0.126USA (Virginia) Megalonyx jeffersonii (104662)
Rancholabrean (glacial)0.3 - 0.012USA (California) Megalonyx jeffersonii (20624)
Rancholabrean0.3 - 0.012USA (South Carolina) Megalonyx jeffersonii (79757 79760)
Late/Upper Pleistocene (late glacial)0.126 - 0.0117USA (Ohio) Megalonyx jeffersonii (93208)
Late/Upper Pleistocene (interglacial)0.126 - 0.0117Canada (Northwest Territories) Megalonyx jeffersonii (20610)
Late/Upper Pleistocene (interglacial)0.126 - 0.0117USA (Idaho) Megalonyx jeffersonii (20569 20612)
Late/Upper Pleistocene (interglacial)0.126 - 0.0117USA (California) Megalonyx jeffersonii (20574)
Late/Upper Pleistocene (high glacial)0.126 - 0.0117USA (Texas) Megalonyx brachycephalus (93103)
Late/Upper Pleistocene0.126 - 0.0117USA (Virginia) Megalonyx jeffersonii (103358 104678)
Late/Upper Pleistocene (late glacial)0.126 - 0.0117USA (North Dakota) Megalonyx jeffersonii (93268)
Late/Upper Pleistocene0.126 - 0.0117USA (Florida) Megalonyx jeffersonii (74292)
Late/Upper Pleistocene (interglacial)0.126 - 0.0117Canada (Yukon) Megalonyx jeffersonii (20626)
Late/Upper Pleistocene (late glacial)0.126 - 0.0117USA (Utah) Megalonyx jeffersonii (93266)
Late/Upper Pleistocene (interglacial)0.126 - 0.0117USA (Alabama) Megalonyx jeffersonii (20584)
Late/Upper Pleistocene0.126 - 0.0117USA (Illinois) Megalonyx jeffersonii (93486)
Late/Upper Pleistocene (late glacial)0.126 - 0.0117USA (Illinois) Megalonyx jeffersonii (93209)
Late/Upper Pleistocene (glacial)0.126 - 0.0117USA (California) Megalonyx jeffersonii (155393)
Late/Upper Pleistocene0.126 - 0.0117USA (Missouri) Megalonyx jeffersoni (93379)
Late/Upper Pleistocene (late glacial)0.126 - 0.0117USA (Kansas) Megalonyx jeffersonii (83073)
Late/Upper Pleistocene - Holocene0.126 - 0.0USA (Missouri) Megalonyx jeffersonii (63563)