The fourth is the aardwolf, which is considered by some not to be a species of hyena at all.
Many people believe that the hyena is from the canine family, which is untrue.
Hyaenidae are found in Africa, South Western Asia, and India. Hyenas range in size from medium to large, and weigh anywhere from 10 to 80 kg. Each species has a distinctive coat, and all hyenas, except for the aardwolf, have massive jaws and large bone crushing teeth. A distinguishing feature of the hyena is the difference in length between the front and rear limbs, which gives them the appearance of always running uphill. In some species of hyena the females have reproductive organs that are incredibly similar to those of males, thereby making them hard to distinguish visually from males.