This is hard to pick. So many great entries.
I really dig the design of hallo's creature and the coloring is really nice. And AndrewLey's work is just outstanding as always. BlueMech has a really fun concept going on there. And the art of shadoman, leckronium, Digisaur and deschcamps are too good to let go. >.<
After the long debate and struggling, I decide to cast my vote for bluefooted. I just love the horns, and the coloring. and it seems to be a very realistic creature too. And the reason for its extinction makes perfect sense.