Oenothera platanorum |
Oenothera linifolia |
|
---|---|---|
Fort Huachuca evening primrose |
threadleaf evening-primrose, threadleaf sundrop |
|
Habit | Herbs perennial, caulescent, strigillose, often densely so; from slender taproot. | Herbs annual, caulescent, strigillose or glabrous, also often glandular puberulent, especially distally; from a sparsely branched taproot. |
Stems | 1–several, ascending, 5–60 cm. |
unbranched or with many ascending branches arising near base, erect, 10–50 cm. |
Leaves | in a basal rosette and cauline, basal 2–7 × 0.3–1.4 cm, blade narrowly elliptic to narrowly ovate, margins weakly serrulate to sinuate-pinnatifid; cauline 1.2–6 × 0.3–1 cm, blade narrowly elliptic to elliptic or ovate, proximal ones sinuate-pinnatifid, margins subentire or weakly serrulate. |
in a basal rosette and cauline, basal 1–2(–4) × 0.2–0.6 cm, petiole 0.2–1(–1.5) cm, blade ovate to obovate or narrowly elliptic; cauline 1–4 × less than 0.1 cm, sessile, blade linear or filiform. |
Inflorescences | erect. |
|
Flowers | 1–3 opening per day near sunrise; buds with free tips 0–0.1 mm; floral tube 9–14 mm; sepals 7.5–13 mm; petals rose purple, fading darker, 8–15 mm; filaments 4–9 mm, anthers 2.5–4 mm, pollen 85–100% fertile; style 12–19 mm, stigma surrounded by anthers at anthesis. |
usually 1–3 opening per day near sunrise; buds without free tips; sepals 1.5–2 mm; petals bright yellow, fading pink, obcordate to obovate, 3–5(–7) mm; filaments 1–2 mm, anthers 0.5–1 mm; style 1–2 mm, stigma surrounded by anthers at anthesis. |
Capsules | clavate or narrowly obovoid, 9–14 × 3–4 mm, apex attenuate to a sterile beak, valve midrib prominent in distal part, proximal stipe 4–15 mm, gradually tapering to base; sessile. |
ellipsoid-rhombic to subglobose, 4-angled, 4–6(–10) × 1.5–3 mm, stipe 0–4 mm, valve midrib raised at distal end, indehiscent or tardily dehiscent distally; sessile. |
Seeds | narrowly obovoid, 0.7–0.9 × 0.3–0.5 mm. |
clustered in each locule, ovoid, surface minutely papillose, 1 × 0.5 mm. |
2n | = 14. |
= 14. |
Oenothera platanorum |
Oenothera linifolia |
|
Phenology | Flowering Mar–Aug. | Flowering Apr–Jun(–Aug). |
Habitat | Streambeds and near springs. | Prairies, open woodlands, open rocky and sandy sites, roadsides. |
Elevation | 700–1900 m. (2300–6200 ft.) | 0–400 m. (0–1300 ft.) |
Distribution |
AZ; Mexico (Sonora) |
AL; AR; FL; GA; IL; KS; KY; LA; MO; MS; NC; OK; SC; TN; TX
|
Discussion | Oenothera platanorum is known only from the southeastern counties of Cochise, Pinal, and Santa Cruz in Arizona. It was recently collected in Sonora, Mexico. The species is very similar to both O. texensis, from which it differs in its smaller flowers, and the widespread O. rosea, from which it differs in the somewhat larger flowers and in forming seven bivalents in meiosis and fully fertile pollen, whereas O. rosea is a PTH species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Kneiffia linearifolia Spach (1835) is an illegitimate name based on Oenothera linifolia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 10. | FNA vol. 10. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Kneiffia linifolia, O. linifolia var. glandulosa, Peniophyllum linifolium | |
Name authority | P. H. Raven & D. R. Parnell: Madroño 20: 246. (1970) | Nuttall: J. Acad. Nat. Sci. Philadelphia 2: 120. (1821) |
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