Seems I recall a giant sloth hide being found by boy scouts near Las Cruces in a cave. It also seems like scientist didn’t think the sloth had been dead more than hundreds of years, not thousands. I don’t know how that story might effect this one.
http://www.gpo.gov/fdsys/pkg/CHRG-111shrg56084/html/CHRG-111shrg56084.htm
[snip] Proposed wilderness areas in Dona Ana County, NM, also contain many significant fossil and mineralogical sites. For example, a mummified Pleistocene-age giant sloth was discovered many years ago by Boy Scouts exploring a fumarole at Aden Crater. The sloth is now in residence at the Smithsonian Institution in Washington, D.C. If that area had been designated as a Wilderness Area at that time, it is likely that the sloth would have remained undiscovered. [/snip]