Unlike horses, however, Diadiaphorus lacked fused limb bones. Its skull was short and had a relatively large brain cavity. Judging from its low molars, Diadiaphorus ate soft vegetation, such as leaves.
Diadiaphorus, unlike horses, possessed unfused limb bones. Its skull was compact with a sizable brain cavity. Based on its tiny molars, it is inferred that Diadiaphorus ate soft plant matter like leaves.