Oligokyphus (meaning "small curved animal"), was a small animal, around 50 centimetres (20 in) in length, belonging to the herbivorous Tritylodontidae family. It resembled a weasel in appearance, with a long and slim body. The limbs sat directly under the body, like modern mammals, but unlike other known synapsids.[1] Oligokyphus was found widely across North America, Europe and China. This indicates that there were substitutes with the terrestrial vertebrates.