Certain parts of the US are reported to have Jaguar, which are gold & black, but sometimes all black. Mountain lions can occasionally be found in black, but it is rare. A lesser known fact is the exotic pet industry produces large amounts of leopards, jaguar, lions, tigers. A lot of these cats are released or escape the often inadequate housing these stupid people keep them in. I myself have seem a medium/small sized black panther. It was a bit bigger than a bobcat but black with a long thick tail like you see on cats like leopards. The good news is that most of these "panthers" don't survive long in the wild (they don't know how to hunt) and are so shy that they seldom cause problems for humans.