Camissonia campestris (Mojave sun cup or Mojave suncup), is a flowering plant

Flowering plant

The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...

 in the family Onagraceae

Onagraceae

Onagraceae, also known as the Willowherb family or Evening Primrose family, are a family of flowering plants. The family includes about 640-650 species of herbs, shrubs, and trees in 20-24 genera...

, native to the Mojave Desert

Mojave Desert

The Mojave Desert occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona, in the United States...

 of the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. 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

Annual plant

An annual plant is a plant that usually germinates, flowers, and dies in a year or season. True annuals will only live longer than a year if they are prevented from setting seed...

 growing to 5-25 cm tall (rarely to 50 cm tall). The leaves

Leaf

A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

 are linear, 0.5-3 cm long, with a finely serrated margin. The flower

Flower

A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...

s have four petals 5-15 mm long, yellow with a red spot at the base, fading orange to reddish.