 "Metamynodon planifrons", the largest species, was about in length and in weight, and, although it was distantly related to modern rhinos, looked more like a hippo ("Hippopotamus amphibius").Its front legs had four toes instead of the three found in modern rhinos.Like other swamp rhinos, "Metamynodon" has large canines, and Metamynodonts generally have larger canines than other swamp rhinos.