On cf Oenothera, although there were only rosettes here and I didn't see anything elsewhere on the hike that looked to be a good candidate for the host species. The rosettes here were all highly infected and dieing. On thin sand over sandstone rocks, with weedy Bromus etc, in epic canyon bottom.
Description
Locally common.
Voucher image
Photos posted on iNaturalist: https://www.inaturalist.org/observations/219244215.