In DragonVale for the Android & iOS devices (iPhone, iPad, etc.) the Bearded Dragon is a limited dragon available around Fathers Day.
The Bearded Dragon has a base breeding time of 15 hours, sells for 1,000,000 coins, and earns 150,000 XP for successful breeding once you reach level 17.
To breed a Bearded Dragon, you just need to breed a Mountain Dragon with a Metal Dragon or other metal hybrid dragon.
Check out my DragonVale Breeding Guide for more dragon breeding combinations.