Calochortus ciscoensis Welsh & Atwood (published in 2008). Atriplex corrugata in background/left, Astragalus convallarius in back/right, Squirrel grass in front of lower/smaller flower. . Plants may include a vey faint (as above) or purple slender chevron or it may be completely lacking. Plants are bunched, usually with several flowers per stem (2 or 3 commonly, or 4-5+), long drooping leaves present at the time of flowering. May 28, 2011, 5015 ft., eastern Duchesne Co., Utah
Calochortus nuttallii Torr. & GrayJune 9, 2008, Salt Lake County foothills, Utah. Utah's state flowerThis is the typical expression of the species, somewhat low, large, often singular flower, appearing singular, prominent chevron/purple blotches in the throat.
This is one of several kinds of Mariposa lilies that start to bloom near the end of Spring. This one has the common name "Golden Nuggets". I was surprised to see on the CalPhotos database that there's quite a variation in appearance in this species. Some have a dark spot on each petal and others have differently shaped stamens.