Oenothera linifolia |
Oenothera demareei |
|
---|---|---|
threadleaf evening-primrose, threadleaf sundrop |
demaree's beeblossom |
|
Habit | Herbs annual, caulescent, strigillose or glabrous, also often glandular puberulent, especially distally; from a sparsely branched taproot. | Herbs usually robust winter-annual, sometimes biennial, densely strigillose throughout; from fleshy taproot. |
Stems | unbranched or with many ascending branches arising near base, erect, 10–50 cm. |
usually well-branched distal to base, 50–400 cm. |
Leaves | 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. |
in a basal rosette and cauline, 3–7 × 0.2–0.8 cm; blade narrowly elliptic to elliptic or lanceolate, margins subentire or shallowly undulate-denticulate. |
Flowers | 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. |
4-merous, zygomorphic, opening at sunrise; floral tube 4–13(–15) mm; sepals 13–20 mm; petals white, fading pink, rhombic-obovate, 10–17 mm; filaments 8–17 mm, anthers 3–7 mm, pollen 90–100% fertile; style 18–32 mm, stigma exserted beyond anthers at anthesis. |
Capsules | 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. |
ellipsoid or ovoid, sharply 4-angled, 4.5–7 × 1.5–2.5 mm; sessile. |
Seeds | clustered in each locule, ovoid, surface minutely papillose, 1 × 0.5 mm. |
2–4, yellowish to reddish brown, 1.2–3 × 0.7–1.3 mm. |
2n | = 14. |
= 14. |
Oenothera linifolia |
Oenothera demareei |
|
Phenology | Flowering Apr–Jun(–Aug). | Flowering Jul–Oct. |
Habitat | Prairies, open woodlands, open rocky and sandy sites, roadsides. | Open meadows in sandy loam. |
Elevation | 0–400 m. (0–1300 ft.) | 70–200 m. (200–700 ft.) |
Distribution |
AL; AR; FL; GA; IL; KS; KY; LA; MO; MS; NC; OK; SC; TN; TX
|
AR |
Discussion | Kneiffia linearifolia Spach (1835) is an illegitimate name based on Oenothera linifolia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Oenothera demareei is known only from Clark, Garland, Hempstead, Howard, Montgomery, Pike, Saline, and Sevier counties. P. H. Raven and D. P. Gregory (1972[1973]) found Oenothera demareei to be self-incompatible. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 10. | FNA vol. 10. |
Parent taxa | Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Peniophyllum | Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Gaura > subsect. Gaura |
Sibling taxa | ||
Synonyms | Kneiffia linifolia, O. linifolia var. glandulosa, Peniophyllum linifolium | Gaura demareei |
Name authority | Nuttall: J. Acad. Nat. Sci. Philadelphia 2: 120. (1821) | (P. H. Raven & D. P. Gregory) W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 212. (2007) |
Web links |