However, it's important to note that:
* The Amur leopard is critically endangered. Its population is estimated to be under 100 individuals.
* Tigers can also be very large, and the Siberian tiger (Panthera tigris altaica) is the largest of the tiger subspecies. It can be heavier than the Amur leopard, but is typically slightly shorter in length.
So, while the Amur leopard is the longest cat, the Siberian tiger could be the heaviest.