Tylocephalonyx (Tylocephalonyx skinneri Coombs 1979)
Sister taxa: none
Time period: Miocene of North America (20.43 to 15.97 Ma)
Size: 2,2 m in length, 180 cm in height, 600kg of weight
Tylocephalonyx is an extinct dome-headed chalicothere from the Miocene in North America. It may have used its "dome" in the same way as the pachycephalosaurs. Tylocephalonyx is related to the modern horse, rhino, and tapir.