There is no such animal called a "panther".
The feline genus "panthera" includes lions, tigers, leopards and jaguars.
Usage of the word:
A "Panther" is a leopard in Africa and Asia.
A "Panther" is a Puma/Cougar/Catamount in N.America.
Additionally, the Puma, the Cougar and the Catamount are different names for the same one animal.