Whipscorpions, Order Uropygi
These arthropods are sometimes called vinegaroons because of the vinegar scented chemical that some species spray from a gland at the base of the tail. This chemical is believed to attack the exoskeleton of potential prey or other arthropod predators. These creatures are little changed from others over 300 million years old and fossilized tracks have been discovered that correspond to species living today.
