Mary River Turtle
(Elusor macrurus)

Found only in the Mary River in Queensland, Australia, the Mary River Turtle is one of the most endangered freshwater turtles in the world — and also one of the most distinctive, thanks to the thick coating of green algae that grows on its head and shell, giving it the appearance of a tiny punk rocker. 

It is also unusual in that it can absorb oxygen directly through specialized organs near its tail, allowing it to stay submerged for up to three days!