In their book Cryptozoology A to Z, Loren Coleman and Jerome Clark discuss some sightings of what could be saber-toothed cats.
They first mention a story recorded by Peter Matthiessen in his book The Cloud Forest, which was published in 1966. They write:
"….. Peter Matthiessen relates a story told to him in Paraguay by a seaman named Picquet. Matthiessen wrote: '[He] described a rare striped cat not quite so large as a jaguar and very timid, which is possessed of two very large protruding teeth: this animal, he said, occurs in the mountain jungles of Colombia and Ecuador, and he has glimpsed it once himself.'"In 1975, a "mutant jaguar" was shot and killed in Paraguay.. It was said to weigh 160 pounds, and had twelve inch long saber teeth. Juan Acavar, a zoologist, examined it, and he said it looked like a Smilodon. Authorities, however, said it was only a jaguar so they wouldn't frighten anyone.
|Saber-toothed cat skull|
They also mention an article in the September, 1998 issue of Science Illustree that mentions a sighting of a saver-toothed cat coming out of a cave in Paraguay. This was said to have happened in 1984.
What are we to make of these reports? The descriptions of the cats certainly sound like saber-toothed tigers. The cats did live in North and South America.
These are also not the only supposed sightings of living saber-toothed cats. In 2014, Karl Shuker posted on article on his blog about sightings of a white cat in China that was said to have long saber teeth.
Maybe saber-toothed cats aren't as extinct as we thought….