DuracellEnergizer said:

ZkinandBonez said:

At least we now know that this isn't a droid. It seems like some kind of armoured lizard creature, kind of similar to a Dewback.
The guy riding it also looks kind of familiar, have we seen him before in any production images? Or did he exist in the SW universe before TFA?

Looks similar to those gas mask-wearing aliens from the Mos Eisley cantina:

That's it, I thought he looked familiar.

http://www.ew.com/article/2015/08/12/star-wars-force-awakens-character-names/2
The alien is apparently named Teebo (played by Kian Shah), and the creature is called a "luggabeast."