Holostigma spirale (Hooker) Spach; Oenothera cheiranthifolia Hornemann ex Sprengel var. nitida (Greene) Munz; O. nitida Greene; O. spiralis Hooker; O. spiralis var. nitida (Greene) Jepson; Sphaerostigma nitidum (Greene) Small; S. spirale (Hooker) Fischer & C. A. Meyer; S. spirale var. clypeatum (H. Léveillé) A. Nelson

Stems primarily herbaceous, usually prostrate or decumbent, moderately strigillose, rarely densely silvery strigillose. Flowers: floral tube 2.1–4.2(–4.8) mm; sepals 4–5.6(–6.7) mm; petals 6–11 mm; episepalous filaments 2.8–4.5 mm, epipetalous filaments 1.5–3 mm, anthers 1–1.5 mm; style 6–9 mm, stigma usually surrounded by anthers at anthesis, rarely exserted beyond anthers. 2n = 14.

Flowering Apr–Aug. Coastal sandy slopes and flats; 0–100 m; Calif., Oreg.

Subspecies cheiranthifolia occurs from Coos Bay, Curry County, Oregon, south to Point Conception, Santa Barbara County, California; on the east shore of San Francisco Bay in Alameda, Contra Costa, and Sacramento counties, California, and on San Miguel, Santa Rosa, Santa Cruz, San Nicolas, and San Clemente islands (P. H. Raven 1969).