Sphaerostigma minus A. Nelson, Bull. Torrey Bot. Club 26: 130. 1899 (as minor); Camissonia minor (A. Nelson) P. H. Raven; Oenothera alyssoides Hooker & Arnott var. minutiflora S. Watson; O. chamaenerioides A. Gray var. torta H. Léveillé; O. minor (A. Nelson) Munz; O. minor var. cusickii Munz; S. alyssoides (Hooker & Arnott) Walpers var. minutiflorum (S. Watson) Small; S. tortum (H. Léveillé) A. Nelson; S. tortum var. eastwoodiae A. Nelson

Herbs densely strigillose, inflorescence often also glandular puberulent. Stems usually well branched from base, 3–30 cm, usually flowering proximally and distally. Leaves cauline, mostly clustered near base, reduced distally, 0.5–2.5 × 0.3–1.5 cm; petiole 0.5–2 cm; blade oblanceolate or narrowly oblanceolate, margins entire or sparsely denticulate. Inflorescences erect. Flowers opening at sunset; floral tube 0.5–1.9 mm, strigillose in proximal 1/2 inside; sepals 0.8–1.8 mm; petals white, fading pinkish, 0.8–1.3 mm; filaments 0.3–1.3 mm, epipetalous filaments shorter than episepalous, sometimes apparently abortive, anthers 0.5–0.8 mm; style 1.2–3.2 mm, sparsely short-villous near base, stigma 0.5–0.6 mm diam., surrounded by anthers at anthesis. Capsules cylindrical and thickened proximally, spreading, contorted, subterete, 10–25 × 0.8–1.2 mm, regularly but tardily dehiscent. Seeds monomorphic, gray, 1.1–1.2 × 0.4 mm, finely reticulate. 2n = 14.

Flowering May–early Jun. Clay or sandy soils, slopes, flats, sagebrush, rabbitbrush, bitterbrush or saltbush shrublands; 700–1800 m; Calif., Colo., Idaho, Nev., Oreg., Utah, Wash., Wyo.

P. H. Raven (1969) determined Eremothera minor to be self-compatible and autogamous. The name Sphaerostigma nelsonii A. Heller is superfluous and pertains here.