Family: Evening primrose (Onagraceae)
Size: 0.5 in. (4 deeply cleft petals, rose to purplish, to 0.5 in wide by 0.25 in long in widely branching clister on flower stalk.
Other names: Scarlet beeblossom, plains gaura, butterflyweed
Notes: Newly opened flowers are light colored, opening in the evenig. By morning the flowers are pink, deepening to reddish as the day progresses. There are 3 species of Gaura in Arizona, all found here.
This plant is found on the Appleton-Whittell Research Ranch Working Check list of flora.