The jaguar is the third-largest feline after the lion and tiger. This big cat belongs to the Panthera genus, class Mammalia, and in fact in the Americas, it is the only Panthera species that is found.Typically, jaguars weigh between 100 to 250 pounds and live for 12 to 15 years in the wild.he jaguar is the third-largest feline after the lion and tiger. This big cat belongs to the Panthera genus, class Mammalia, and in fact in the Americas, it is the only Panthera species that is found.