The biggest feature of the Mary River tortoise, which grows in fresh water, is its green hair. These are nothing but clusters of algae growing above the head and shell. The Mary River tortoise is the only species in its genus. All other species disappeared from the evolutionary history of Australia 40 million years ago.
In the 1960s and ’70s, Mary River tortoise cubs were sold in pet stores around Victoria, known as the “penny tortoise” or “pet shop turtle.” This is how the species came to the attention of Sydney turtle researcher John Kahn. It took John more than 20 years to find the source of the baby turtles sold at Victorian pet stores. After several failed attempts, he found the source in the Mary River.
Two finger-like tumors hang from the chin, which breathe through gill-like organs in its genitals and the vertical stripes of algae on the head look like hair. This strange and wonderful creature is threatened with extinction.
The collection of eggs for the tortoise trade has led to the extinction of this species. In addition, the tortoise takes extraordinary time to reach sexual maturity. They do not breed before the age of 25 years. The Mary River tortoise is the second most endangered freshwater tortoise in Australia, after the western swamp turtle (Pseudomonas umbrella) in Western Australia.