The African softshell turtle, also known as the Nile softshell turtle is a large aquatic turtle.
African softshell turtle or Nile softshell turtle (Trionyx triunguis), Toronto Zoo.
African softshell turtles live in freshwater as well as in brackish and saltwater in Africa and the Middle East as well as in the surrounding ocean. African softshell turtles are ambush predators that spend most of their time under water waiting for prey to come buy. African softshell turtles will eat all sorts of small animals as well as fruits seeds and nuts.
African softshell turtles, as most turtles in the family Trionychidae, can stay underwater for prolonged periods of time. Submerged trionychid turtles can breathe air through their snorkel-like nose or if in deeper water they can get oxygen directly from the water through the capillary rich area in their mouth as well as absorbing some oxygen from the water through their skin.
Further Readings:
Nile Soft-Shelled Turtles, Trionyx triunguis.
Trionychidae on Wikipedia.
African softshell turtle on Wikipedia.