Mirabilis bigelovii  Desert Wishbone Bush
PERENNIAL HERB.  A semi-erect, shrubby plant with a tangle of long stems bearing opposite heart-shaped leaves.  Flowers and new growth appear in March-April and again after summer rains; plants may drop their leaves during the driest weeks of summer.  Flowers are white with pink centers and are extremely ephemeral, opening only in bright sunlight and often lasting for less than a day.  In the Empires, uncommon on semi-shaded rock outcrops.
FAMILY:  Nyctaginaceae (Four O'Clock Family)