Oenothera scapoidea Torrey &A. Gray var. eastwoodiae Munz, Amer. J. Bot. 15: 234. 1928 (as eastwoodae); Camissonia eastwoodiae (Munz) P. H. Raven; O. eastwoodiae (Munz) P. H. Raven

Herbs annual, succulent, glabrous, glandular puberulent, or villous proximally. Stems unbranched or branched from base, 3–30 cm. Leaves primarily in basal rosette and also cauline; petiole 0.5–8 cm; blade usually not pinnately lobed or, if so, then lateral lobes greatly reduced, terminal lobe oblanceolate to cordate, 0.8–7.5 × 0.4–3 cm, margins entire or sparsely denticulate, pale brown oil cells lining veins abaxially. Racemes nodding, elongating after anthesis. Flowers opening at sunrise; buds without subapical free tips; floral tube 2–4.5 mm, villous inside proximally; sepals 3–8 mm; petals bright yellow, with red dots near base, fading pale yellow or yellowish orange, 5.5–9 mm; stamens unequal, filaments of antisepalous stamens 3–8 mm, those of antipetalous ones 2.8–5.5 mm, anthers 2–4 mm, ciliate; style 10–17 mm, stigma exserted beyond anthers at anthesis. Capsules erect, spreading, or slightly reflexed, clavate, 18–40 mm; pedicel 4–28 mm. Seeds 1.2–1.7 mm. 2n = 14.

Flowering Apr–Jun. Clay flats, on gray, alkaline, marine-deposited gumbo, sandy draws; of conservation concern; 1200–1800 m; Colo., Utah.

Chylismia eastwoodiae is known from Mesa County, Colorado, and from Emery County south to San Juan County, Utah. P. H. Raven (1962, 1969) suspected this species to be self-incompatible, but did not have data to make the determination.