I’ve been looking for it and haven’t found a clear answer, for example “豹” appears as panther in some pages but in others that translates to leopard, I’ve also seen “豹属” as panther
A short answer is that you could use 豹 if you mean the animal with round spots on its skin.
In Japanese, 豹 is a species under the genus 豹属. Normally 豹 makes us think of spotted yellow skin (e.g. ヒョウ柄) and there is a specific word 黒豹 to refer to black leopards/panthers. So as a name of the species, 豹 corresponds to the English leopard. If you mean black leopards by panther, then there is no common single kanji for it.