Fitzroy River Turtle

Rheodytes leukops
 
These turtles are affectionately known as ‘bum breathers’. They are the sole surviving member of a previously more widespread genus, now confined to the Fitzroy catchment. Rheodytes possess a cloacal cavity made up of bursae filled with vascularized fimbriae allowing for oxygen uptake from water via diffusion. This specialized structure is surrounded by muscles that contract the bursae—the ultimate bum-breathing adaptation—at 15-60 'bum breaths' per minute, allowing Rheodytes to stay submerged for days at a time.