Vinegaroons have heavy mouthparts (pedipalps) that are formed into pincers. The first pair of legs is long and thin and is used like antenna to feel their way around. The next three pairs of legs are used for walking.
The abdomen is attached widely to the head-thorax region (cephalothorax). The tail is long and thin suggesting a whip which is where the common name, “whipscorpion”, originates for the order Uropygi. The only species that occurs in Texas is Mastigoproctus giganteus (Lucas) which is a vinegaroon in the family Thelyphoridae. Our Texas species is nearly black in color. Bodies of adults are 1 ½ to 3 inches long. It is found primarily in west Texas especially in the Trans-Pecos region but has been reported as far north as the Panhandle and in south Texas.