A hoop snake is a creature whose existence is just a legend or myth. It is supposed to be a dangerous snake that is able to form itself into a hoop shape and roll around like a wheel. This story seems to be told primarily in North America, although versions of it also are told in Australia. The existence of the hoop snake has never been proven, but the story still persists.
According to legend, the hoop snake at times appears just like any other snake. Its unique feature is the ability to form itself into a hoop shape by biting its own tail and holding it in its mouth, keeping the rest of its body rigid at the same time. Once in this position, it is supposed to be able to roll around like a wheel or a hula hoop on its side. While doing this, the hoop snake can move much faster than an ordinary snake, making it quite dangerous. There are many tales of the snake using this ability to chase down human prey. It is said only to do this while attacking, not while trying to escape from predators.
Some versions of the story talk about the hoop snake also having a poisonous stinger at the end of its tail. In these versions of the story, once the creature catches up with its prey it uses this stinger to kill its victim. Some variations have the snake rolling along looking for a victim, then quickly striking out with its tail at an unsuspecting person. Others have the snake stopping its motion and straightening out at the last minute, using the tail more like a spear. The only way to escape death from the hoop snake's poisonous tail is supposed to be by hiding behind a tree, so the poison kills the tree instead.
A few people theorize that the legend may have been inspired in North America by a habit of the common mud snake, which often lies in the sun with its body coiled very loosely, in a shape similar to a hoop. Some think it may have been inspired by the ancient ouroboros symbol, which shows a serpent or dragon in a circular shape, swallowing its own tail. This symbol is said to represent the cyclical nature of many things. Whatever its origin, there are still occasional hoop snake sightings reported, in spite of the fact that scientists have never confirmed its existence.