Eisenhower_Yucca_Trail
First two pics show two species for comparative purposes.
Specimen on right: Note V-shaped base of flower, less dense branching, longer/narrower petals compared to Amphiachris (left; https://www.inaturalist.org/observations/34926032).
These specimens were growing adjacent to one another in the same soil type (a silty, firm sandy loam).
The butterfly flew away before I could photograph her