Camissonia micrantha is a species of flowering plant in the evening primrose family known by the common name miniature suncup. It is endemic to California, where it grows along the coast and in the coastal mountains as far north as the San Francisco Bay Area, as well as in the Central Valley. It grows in sandy areas in a number of habitats, from beaches to inland slopes. This is a small, hairy annual herb producing a basal rosette of leaves. The stem varies in morphology, approaching half a meter in erect height or quite short and flat, with or without branching. The larger leaves are located in the basal rosette; those on the stem are narrow and shorter. The flower cluster produces bears a number of flowers with petals less than 5 millimeters long. They are bright yellow and dry to a reddish color as they close. If the flower cluster is located on an erect stem it bends the stem over with its weight. The flowers self-pollinate. The fruit is a cylindrical capsule 1 to 2 centimeters long.