Turtle
Aquatic respiration in Australian freshwater turtles is being studied. Some species have large cloacal (the hole used for mating and excretion) holes that are lined with many finger-like projections. These projections, called papillae, have a rich blood supply, and increase the surface area of the cloaca. The turtles can take up oxygen from the water using these papillae, in much the same way that fish use gills to take in oxygen.