Natural Phenomenon: Great Lake Giant Limpet
Summary
The Great Lake Giant Limpet (Ancylastrum cumingianus) was once a common Tasmanian endemic species, now thought to be extinct.
Details
Called a limpet because it is shaped like the common sea-shore limpets, this freshwater snail was only known from the Great Lake area of the Central Highlands. It was so common in the mid-1800s that specimens were sent to many natural history museums around the world as the largest freshwater limpet in the world. The shells are up to about 12 mm in width, while ordinary freshwater limpets are only about 4 mm in length. Only a few specimens have been seen in the last 35 years, all taken from the stomach of the introduced fish, the trout.
Brian J Smith