According to this press release, a carving of a mammoth was incised on a bone fragment discovered at an archaeological site in Florida. This is an exciting discovery, and the first such image found on a bone in the Americas. However it is a little extreme to claim, as the press release does, that this is the only known image of a proboscidean (aka animals with trunks – elephant relatives) found in the Americans. There are at least three petroglyphs in Utah that appear to depict mammoths or mastodons, one of which I blogged about a while back.
Still, Pleistocene-era art in the Americas is extremely rare, and this is a remarkable find.