Camissonia campestris

Camissonia campestris (field primrose,: 238  Mojave sun cup,: 238  or Mojave suncup), is a flowering plant in the family Onagraceae, native to the Mojave Desert of the United States. It grows mostly on open, sandy flats, occurring from sea level to 2,000 m in the western and central part of the desert. It is an annual plant growing to 5–25 cm tall (rarely to 50 cm tall). The leaves are linear, 0.5–3 cm long, with a finely serrated margin. The flowers have four petals 5–15 mm long, yellow with a red spot at the base, fading orange to reddish....read more on Wikipedia.