Xenarthra

Xenarthrans
Temporal range: Late Paleocene –Recent, 60–0 Ma
Clockwise from upper leff: Megatherium, giant anteater, two-toed sloth, nine-banded armadillo.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Infraclass: Placentalia
Superorder: Xenarthra
Cope, 1889
Orders and suborders


See text for more details

Red: anteater, yellow: armadillo, blue: sloth, orange: both anteater and armadillo, green: both armadillo and sloth, purple: anteater, armadillo and sloth

Xenarthra (/zɛˈnɑːrθrə/; from Ancient Greek ξένος, xénos, "foreign, alien" + ἄρθρον, árthron, "joint") is a major clade of placental mammals native to the Americas. There are 31 living species: the anteaters, tree sloths, and armadillos.[1] Extinct xenarthrans include the glyptodonts, pampatheres and ground sloths. Xenarthrans originated in South America during the late Paleocene about 60 million years ago.[2] They evolved and diversified extensively in South America during the continent's long period of isolation in the early to mid Cenozoic Era. They spread to the Antilles by the early Miocene and, starting about 3 million years ago, spread to Central and North America as part of the Great American Interchange.[3] Nearly all of the formerly abundant megafaunal xenarthrans became extinct at the end of the Pleistocene.

  1. ^ Vizcaíno, Sergio F.; Loughry, W. J., eds. (2008). The biology of the Xenarthra. Gainesville: University Press of Florida. ISBN 978-0-8130-3718-9. OCLC 741613153.
  2. ^ O'Leary, M. A.; Bloch, J. I.; Flynn, J. J.; Gaudin, T. J.; Giallombardo, A.; Giannini, N. P.; Cirranello, A. L. (2013). "The placental mammal ancestor and the post–K-Pg radiation of placentals". Science. 339 (6120): 662–667. Bibcode:2013Sci...339..662O. doi:10.1126/science.1229237. hdl:11336/7302. PMID 23393258. S2CID 206544776.
  3. ^ Woodburne, Michael O. (2010). "The Great American Biotic Interchange: Dispersals, Tectonics, Climate, Sea Level and Holding Pens". Journal of Mammalian Evolution. 17 (4): 245–264. doi:10.1007/s10914-010-9144-8. PMC 2987556. PMID 21125025.