posted 08/15/14 - I've tried numerous times from late July to mid-August to get a clear picture of this fun bee mimic that hovers like a hummingbird. Unfortunately, the CA clearwing moth usually finishes feeding at a flower the split second before my auto-focus sets, to then move around to the privacy of a bloom opposite the stalk to me. It then becomes a game of ring around the odoriferous vinegar weed. Sigh. I end up smelling vinegar weed for the rest of my hike, too often from a carelessly dangled camera strap. Ah, good times. Smelly. But, good.
For those not hip to the taxonomic tricks (like me), western Hemaris thetis was split off from eastern Hemaris diffinis (7855) in 2009.