Dragon

The dragon was the largest native Safeholdian land-based life form. The term was applied to two un-related species, the common dragon and the great dragon.

The common dragons was about twice the size of a Terran elephant and a herbivore. Other than its name would make one suspect, the great dragon was smaller than the common dragon, and not actually related to it. The two varieties looked very much alike, aside from their different teeth and jaws. Like all higher life forms on the planet, they were hexapedal. 

By the 9th Century of God, dragons were professionally bred by humans. 

Dragons were almost as efficient as oxen when it came to drawing weights. (MTAT)

Dragonpower was a measure of power based upon the capablilties of Dragons. (MTAT)