While a variety of mammalian megafauna have been recovered from sediments associated with Lake Bonneville, Utah, sloths have been notably rare. Three species of ground sloth, Megalonyx jeffersonii, Paramylodon harlani, and Nothrotheriops shastensis, are known from the western United States during the Pleistocene. Yet all 3 are rare in the Great Basin, and the few existing records are from localities on the basin margin. The recent discovery of a partial skeleton of Megalonyx jeffersonii at Point-of-the-Mountain, Salt Lake County, Utah, fits this pattern and adds to our understanding of the distribution and ecology of this extinct species. Its occurrence in Lake Bonneville shoreline deposits permits a reasonable age determination of between 22 and 13 ka.
McDonald, H. Gregory; Miller, Wade E.; and Morris, Thomas H.
"Taphonomy and significance of Jefferson's ground sloth (Xenarthra: Megalonychidae) from Utah,"
Western North American Naturalist: Vol. 61
, Article 9.
Available at: http://scholarsarchive.byu.edu/wnan/vol61/iss1/9