9. Megapiranha : The Rivers Of Dread
Around eight to ten million years ago, the late Miocene era was plagued by the presence of Megapiranha in the rivers of South America. These carnivorous fish were truly gigantic, growing up to 28 inches in length and weighing around 22 pounds. With a bite force estimated to be equivalent to that of a small great white shark, encountering these formidable creatures in the water would have been a true nightmare.
