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The Tremarctinae or short-faced bears is a subfamily of Ursidae that contains one living representative, the spectacled bear (Tremarctos ornatus) of South America, and several extinct species from four genera: the Florida spectacled bear (Tremarctos floridanus), the North American short-faced bears of genera Plionarctos (P. edensis and P. harroldorum) and Arctodus (A. pristinus and A. simus), and the South American giant short-faced bears of Arctotherium (including A. angustidens, A. vetustum, A. bonariense, A. wingei, and A. tarijense).[1]

Temporal range: late Miocene–present
Spectacled Bear Tennoji 2.jpg
A spectacled bear in Tennōji Zoo, Osaka.
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Ursidae
Subfamily: Tremarctinae
Merriam & Stock, 1925



Traditionally the phylogenetic inner relationships of tremarctines had Plionarctos and Tremarctos being basal groups with respect to a short-faced bear clade of Arctodus and Arctotherium.[2][3] A study of the affinities of bears belonging to Arctotherium indicates that they were more closely related to the spectacled bear than to Arctodus.[4]


The following taxonomy of the tremarctine bears follow by Mitchell et al. (2016)[4]:

  • Subfamily Tremarctinae (Merriam & Stock, 1925)
    • Plionarctos (Frick, 1926)
      • Plionarctos harroldorum (Tedfored & Martin, 2001)
      • Plionarctos edensis (Frick, 1926)
    • Arctodus (Leidy, 1854)
      • Arctodus simus (Cope, 1879)
      • Arctodus pristinus (Leidy, 1854)
    • Arctotherium (Burmeister, 1879)
      • Arctotherium angustidens (Gervais & Ameghino, 1880)
      • Arctotherium vetustum (Ameghino, 1885)
      • Arctotherium wingei (Ameghino, 1902)
      • Arctotherium bonariense (Gervais, 1852)
      • Arctotherium tarijense (Ameghino, 1902)
    • Tremarctos (Gervais, 1855)

See alsoEdit


  1. ^ Krause, J.; Unger, T.; Noçon, A.; Malaspinas, A.; Kolokotronis, S.; Stiller, M.; Soibelzon, L.; Spriggs, H.; Dear, P. H.; Briggs, A. W.; Bray, S. C. E.; O'Brien, S. J.; Rabeder, G.; Matheus, P.; Cooper, A.; Slatkin, M.; Pääbo, S.; Hofreiter, M. (2008-07-28). "Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary". BMC Evolutionary Biology. 8: 220. doi:10.1186/1471-2148-8-220. PMC 2518930. PMID 18662376.
  2. ^ Soibelzon, Leopoldo H.; Rincón, Ascanio D. (2007). "The fossil record of the short-faced bears (Ursidae, Tremarctinae) from Venezuela. Systematic, biogeographic, and paleoecological implications". Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 244 (3): 287–298. doi:10.1127/0077-7749/2007/0244-0287.
  3. ^ Soibelzon, Leopoldo H.; Schubert, Blaine W. (2011). "The largest known bear, Arctotherium angustidens, from the early Pleistocene pampean region of Argentina: with a discussion of size and diet trends in bears". Journal of Paleontology. 85 (1): 69–75. doi:10.1666/10-037.1.
  4. ^ a b Kieren J. Mitchell, Sarah C. Bray, Pere Bover, Leopoldo Soibelzon, Blaine W. Schubert, Francisco Prevosti, Alfredo Prieto, Fabiana Martin, Jeremy J. Austin and Alan Cooper (2016). "Ancient mitochondrial DNA reveals convergent evolution of giant short-faced bears (Tremarctinae) in North and South America". Biology Letters. 12 (4): 20160062. doi:10.1098/rsbl.2016.0062. PMC 4881349. PMID 27095265.CS1 maint: uses authors parameter (link)

External linksEdit