OK, so let's clear this up. A jaguar (Panthera onca) is one of those spotty jobs who live in trees and eat children and deer but live in South and Central America. A leopard (Panthera pardus) is smaller than a jaguar but still eats deer and children and live up trees. However, leopards live in Africa and Asia. A panther, meanwhile, can be either of them. Or indeed any other big cat, such as a tiger (Panthera tigris), with the recessive gene which causes melanism, i.e. black colouration.
So, J is for that.
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