Oenothera elata |
Oenothera argillicola |
|||||
---|---|---|---|---|---|---|
evening primrose, Hooker's evening-primrose, western evening primrose |
shale barren evening primrose |
|||||
Habit | 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. | Herbs biennial or short-lived perennial, strigillose and sparsely to moderately villous, hairs sometimes pustulate, pustules with green or red bases, inflorescence glabrous or sparsely glandular puberulent, sometimes also sparsely villous. | ||||
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. |
erect to ascending, green or red, unbranched or with branches obliquely arising from rosette or in distal 1/2 of main stem. |
||||
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. |
in a basal rosette and cauline, basal 7–25 × 0.7–2 cm, cauline 6–13 × 0.4–1 cm; blade dark green, somewhat glossy, very narrowly oblanceolate to narrowly oblanceolate, linear-elliptic, lanceolate, or nearly linear, margins flat, entire or remotely and bluntly dentate, sometimes with larger teeth near base; bracts persistent. |
||||
Inflorescences | erect, unbranched. |
curved with ascending tip, 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. |
opening near sunset; buds erect, 4–8 mm diam., with free tips subterminal, divergent and hornlike, 3–9 mm; floral tube 32–52 mm; sepals yellowish green to yellow, sometimes flushed with red, especially at apex, 27–38 mm; petals yellow to pale yellow, fading pale yellow to pale yellowish orange, very broadly obcordate or obovate, 25–42 mm; filaments 20–27 mm, anthers 9–13 mm, pollen 90–100% fertile; style 60–85 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. |
spreading at nearly a right angle to stem, curved upward, sometimes secund, dull green or rusty brown when dry, narrowly lanceoloid to lanceoloid, 20–40 × 4–6 mm, free tips of valves 1–2 mm. |
||||
Seeds | 1–1.9 × 0.6–1.2 mm. |
1.3–1.9 × 0.7–1.1 mm. |
||||
2n | = 14. |
|||||
Oenothera elata |
Oenothera argillicola |
|||||
Phenology | Flowering (Jun–)Jul–Oct. | |||||
Habitat | Open sites on Devonian Brallier shale slopes, barrens, outcrops or adjacent roadsides in mid-Appalachian Allegheny Mountains. | |||||
Elevation | 150–700 m. (500–2300 ft.) | |||||
Distribution |
w United States; c United States; Mexico; Central America
|
MD; PA; VA; WV |
||||
Discussion | 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. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Oenothera argillicola is one of eight angiosperm species restricted to the Devonian Brallier shale barrens, but among them only O. argillicola and Trifolium virginicum occur throughout the shale barren region. Oenothera argillicola has plastome V and a CC genome composition. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||
Key |
|
|||||
Source | FNA vol. 10. | FNA vol. 10. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | O. argillicola var. pubescens | |||||
Name authority | Kunth in A. von Humboldt et al.: Nov. Gen. Sp. 6(fol.): 72; 6(qto.): 90. (1823) | Mackenzie: Torreya 4: 56. (1904) | ||||
Web links |
|