it does not ya have to trade him
When you hit it with a clampearl
Rhyhorn evolves to Rhydon at Lv-42. Rhydon evolves to Rhyperior via trade (with a Protector).
rhydon does not evolve by leveling it up it has to be traded holding a protecter hope i helped
Rhydon evolves when you trade it while holding a protector.