The Iridescent Shark, also known as the Pangasius Catfish, is a freshwater fish with a shark-like appearance and an iridescent sheen on its skin. Despite its name, it is not a true shark but a catfish. These fish are known for their size, reaching up to 4 feet in length, and their skittish nature. They are native to Southeast Asia, particularly the Mekong and Chao Phraya rivers.