Semi-desert. Shrublands, Pinyon/Juniper woodlands, sand, rocks. Spring.
Colorado River near Moab, May 5, 2005.

Normally Camissonia walkeri leaves are "bright gray-green... and peppered with small darker green spots" (Intermountain Flora) or "purple dotted" (Utah Flora). 

Apparently the soil in the area of the pictured plants imparts the fabulous turquoise.  Camissonia walkeri could easily be mistaken for a Mustard (I mistook it at first) but a closer look, especially at the flower, shows it to be an Evening Primrose.

The renowned Charles Parry collected this in the Virgin River valley near St. George, Utah in 1874 and Aven Nelsen named it Oenothera brevipes in 1875.  Nelsen renamed it Chylisma walkeri in 1913, it went through several other name changes, and Peter Raven, now Director of the Missouri Botanical Garden, renamed it Camissonia walkeri in 1964.  Ernest P. Walker collected the species in the Paradox Valley of Colorado in 1912.  (More biographical information.)

Semi-desert. Shrublands, Pinyon/Juniper woodlands, sand, rocks. Spring.
Colorado River near Moab, May 5, 2005.

Flowers are quite small; seed pods are large, ribbed, and arching upward on short stems.

Semi-desert. Shrublands, Pinyon/Juniper woodlands, sand, rocks. Spring.
Colorado River near Moab, May 5, 2005.

Minute buds give way to tiny flowers which give way to long seed pods.