Very, very alien.
This is another Small Phigalia (I think). He wouldn't let me open up his wings to get a peek at the hind wings, but he was much more obliging about hanging out on my finger as I dashed from light source to light source, trying to get the best shot.
Here's the gently patterned back. I guess I need to get one of these in daylight so I can try to capture that beautiful soft pewter shine; the flash brings out the glare of the scales. I believe the two dots along the edge of the wing and towards the body point to this being a Small Phigalia.