Amazon Rainforest Animals: The Jaguar. The jaguar or Panthera onca, is a big cat, a feline in the Panthera genus, and is the only Panthera species found in the Americas. The jaguar is the third-largest feline after the tiger and the lion, and the largest in the Western Hemisphere.he Amazon Rainforest is the largest rainforest in the world. The Amazon Rainforest is of great significance to the climate of the world because it absorbs very large amounts of carbon dioxide present in the atmosphere. The Amazon Rainforest is also home to many unique animals.