The Tubarão-cabeça-chata, Tubarão-de-cabeça-chata, Tubarão-touro ou Tubarão-do-zambeze is a shark of the order Carcharhiniformes that can live in both saltwater and freshwater. Reaches 2 m to 3.5 m long. Their coloration ranges from brown back to dark gray with white belly. It feeds on fish, including other sharks, rays and birds. They are found near the back of the beaches, but can live for a time in rivers and lakes. It has been found in the Amazon River. They are also the main species to attack humans in riverine areas, thanks to their ability to live in low salinity. Moreover, they have very poor vision, depending on other senses to attack, what makes this extremely dangerous shark in waters of poor visibility. They live at a depth of 30 meters or even less than 3 meters.