Sun cups are low, ± prostrate, reddish-stemmed annuals to short-lived perennials. The older stem epidermis often exfoliates.  There is a basal rosette of narrowly-elliptic pubescent to pilose green leaves on petioles to 1-1/2" long, and the upper leaves are alternate and lanceolate-linear, minutely dentate to subentire, and almost sessile.  The flowers are about an inch across and arise from the leaf axils, with an inferior ovary, four down-turned sepals, and four bright yellow petals with a dark red to maroon spot at the base.  The four epipetalous stamens (that is, those attached to the petals) are shorter than the free ones, and the round stigma is held well above the anthers.  The fruit is an elongated, linear, quadrangular capsule either blunt-tipped or with a beak, and often curved or contorted at maturity.  Sun cups is a fairly common resident of sandy and disturbed or burned areas, clay soils in valley grasslands, coastal strand, and openings in coastal sage scrub and chaparral.  It blooms from March to June. These pictures were taken at the Santa Fe Dam Natural Area in the alluvial fan of the San Gabriel River.

Click here for Latin name derivations: 1) Camissonia 2) bistorta.
Pronunciation: kam-is-OWN-ee-a bis-TOR-ta.
Click here for Botanical Term Meanings.