Camissoniopsis cheiranthifolia, the beach suncup or beach evening primrose, is a species of the evening primrose family and is native to open dunes and sandy soils of coastal California, Baja California and Oregon.

It forms long stems growing from a central crown, lined with silvery grey-green leaves.

The prostrate form and swinging stems allow the plant to survive well on the windy, shifting sands of the coast.

The four-petalled flowers open in the morning (typical among suncups) and are bright yellow, fading to reddish.

This plant is a well-defined diploid (2n = 14) species that has varying floral traits over its geographic distribution.