I couldn't find a picture sharing forum, and this said art post and since this is art I thought it was the right place.
I didn't claim ownership of it and I don't know who made it. You don't say you made your Ampharos avatar, right? (I'm assuming you didn't make it, it looks like the official sprite.) So I think it's okay.
I skimmed through the rules before I posted to make sure it was okay, and I didn't see anything saying I couldn't. It just said not to claim other people's art as mine.
No, your right, the sprites ain't mine.
But, however I ripped them and animated them myself using flash, so I can use it as my avatar.