Journal of Mammalian Evolution

, Volume 24, Issue 2, pp 179–191 | Cite as

Baraguatherium takumara, Gen. et Sp. Nov., the Earliest Mylodontoid Sloth (Early Miocene) from Northern South America

  • Ascanio D. RincónEmail author
  • Andrés Solórzano
  • H. Gregory McDonald
  • Mónica Núñez Flores
Original Paper


We report a new genus and species of sloth, based on a partial mandible and associated femur, from the early Miocene of Venezuela. Baraguatherium takumara, gen. et sp. nov., represents the earliest member of the Mylodontoidea recognized from northern South America. Phylogenetically and morphologically, Baraguatherium possesses some plesiomorphic characters: a vasodentine layer in the core of the tooth similar to Octodontotherium, Paroctodontotherium, and Orophodon; molariforms parallel to the long axis of the toothrow; teeth with a very thin layer of cementum; mf1-mf3 series of similar size and bilobate; mf3 conspicuously piriform; and occlusal surface of tooth beveled, which places it at the base of the Mylodontidae clade. Baraguatherium was found in continental deposits that also preserve abundant wood and leaves associated with a near shore marine complex, indicating that Baraguatherium lived in a coastal tropical forest in the early Miocene in northern South America. The presence of a vasodentine layer in the core of the tooth is quite similar to Octodontotherium, Paroctodontotherium, and Orophodon and allows assignment of this new taxon to the Mylodontoidea.


Baraguatherium takumara Castillo Formation Early miocene Venezuela Sloth diversity 



We wish to thank the Instituto del Patrimonio Cultural (IPC), Venezuela, for fossil collection permissions to this project. We thank Sr. P. Gómez†, Ing. M.E. Mendoza, Lic. M. López, and Dr. F. Urbani for their help and camaraderie during the field trips. The major funding support of this work was provided by Centro de Ecología, Instituto Venezolano de Investigaciones Científicas (IVIC) grant 1096 to A.D.R. Also, we thank to B. Shockey and an anonymous reviewer for all the improvements to that manuscript.


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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Ascanio D. Rincón
    • 1
    Email author
  • Andrés Solórzano
    • 1
  • H. Gregory McDonald
    • 2
  • Mónica Núñez Flores
    • 1
  1. 1.Laboratorio de Paleontología–Centro de EcologíaInstituto Venezolano de Investigaciones Científicas (IVIC)CaracasVenezuela
  2. 2.Bureau of Land Management, Utah State OfficeSalt Lake CityUSA

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