I'm puzzling over field guides that attempt to describe the differences between Clodius Parnassian and Rocky Mountain Parnassion. Rocky Mountain Parnassian, as described by Guppy and Shepard, matches this image (ringed attenae, varying shades of gray/black on dorsal wing surfaces) better than Clodius Parnassian. I'm curious if the location where this photo was taken would provide any additional insights.
