Nov. Gen. Sp. 6(fol.): 72; 6(qto.): 90. 1823.
Herbs biennial or short-lived perennial, densely strigillose and either sparsely or moderately villous, with appressed or spreading hairs (sometimes with red-pustulate bases), distally sometimes also glandular puberulent. Stems erect, green, flushed with red proximally or red throughout, unbranched or branches obliquely arising from rosette and secondary branches arising from main stem, 30–250 cm. Leaves in a basal rosette and cauline, basal 10–43 × 1.2–4(–6) cm, cauline 4–25 × 1–2.5(–4) cm; blade dull green to grayish green, rarely red, narrowly oblanceolate or oblanceolate to narrowly elliptic or narrowly lanceolate, margins usually flat, rarely undulate, bluntly dentate or subentire, teeth sometimes widely spaced, proximal blades sometimes sinuate-dentate toward base; bracts persistent. Inflorescences erect, unbranched. Flowers opening near sunset; buds erect, 6–10 mm diam., with free tips terminal, erect, 1–7 mm; floral tube (20–)30–45(–50) mm; sepals yellowish green, red-striped or strongly flushed with red, 27–50 mm; petals yellow to pale yellow, fading orange or pale yellow, very broadly obcordate, (25–)30–47(–55) mm; filaments 17–25 mm, anthers 8–23 mm, pollen 90–100% fertile; style 50–90 mm, stigma exserted beyond anthers at anthesis. Capsules erect or slightly spreading, dull green or gray-green when dry, narrowly lanceoloid, 20–65 × 4–7 mm, free tips of valves 0.5–2.5 mm. Seeds 1–1.9 × 0.6–1.2 mm.
c, w United States, Mexico, Central America.
Subspecies 3 (2 in the flora).
Subspecies elata differs in anthers 7–12 mm, fewer or no pustulate-based hairs, and generally smaller flowers and habit. It ranges from the highlands of central Mexico, including Guanajuato, Hidalgo, México, Michoacán, Puebla, Querétaro, and Veracruz, south to Guatemala, El Salvador, Costa Rica, and Panama.
Oenothera elata has plastome I and a AA genome composition. Onagra kunthiana Spach is a superfluous name that pertains here.
|1||Plants strigillose, usually also villous, with appressed or spreading hairs, sometimes these with red-pustulate bases, distally sometimes also glandular puberulent; buds green to yellowish green, red-striped, or sometimes red throughout; anthers 8–15(–20) mm.||Oenothera elata subsp. hirsutissima|
|1||Plants strigillose, also villous with appressed or spreading hairs, usually these with conspicuous red-pustulate bases, also glandular puberulent; buds flushed with red; anthers 12–23 mm.||Oenothera elata subsp. hookeri|