Actually, I think that's more like concept art for Ganondorf... Actually, I'm pretty sure that IS concept art for Ganondorf. Seeing how that's Ganondorf, I don't think he would fit anywhere in Skyward Sword, considering the story.
It is an art concept, its one from the Hyrule Historia, but just looking at it, I think the concept looks like it was made for skyward sworde which is ironic because it came from a concept art from twilight princess.
Oh, I get you now. Still, personally I don't really think he could fit anywhere in Skyward Sword. He looks more final boss material to me, and we already have Demise.