Oenothera glaucifolia |
Oenothera mexicana |
|
---|---|---|
false gaura |
Mexican evening primrose |
|
Habit | Herbs probably biennial, glabrous, becoming sparsely to densely glandular puberulent and short-villous distally, glaucous at least in proximal parts; from stout roots. | Herbs annual, moderately to sparsely strigillose and densely long-villous, sometimes also becoming glandular puberulent distally. |
Stems | erect, branched or unbranched, 30–300 cm. |
erect to ascending, usually unbranched, or with arcuate lateral branches arising from rosette, 15–40(–60) cm. |
Leaves | in a basal rosette and cauline, basal 3–7 × 0.5–2 cm, sessile, blade oblong to oblong-lanceolate, base usually ± auriculate, margins entire; cauline 3–8(–10) × 0.4–1.8 cm, blade lanceolate to oblong-lanceolate, gradually smaller, becoming linear-subulate distally. |
in a basal rosette and cauline, basal 6–10 × 1–2.5 cm, cauline 3–7.5 × 0.8–2 cm; blade usually grayish green, narrowly oblanceolate to narrowly oblanceolate, margins deeply lobed, lobes usually dentate; bracts distalmost erect, revolute. |
Inflorescences | long, wandlike, unbranched or branched. |
|
Flowers | 4-merous, nearly actinomorphic, opening near sunrise; floral tube 6–17 mm; sepals 4–6 mm; petals white, fading off-white or tinged pink, slightly unequal, rhombic, 4–6 mm, abruptly clawed; filaments 5–8 mm, anthers 1.5–2 mm, pollen 85–100% fertile; style 6–10, stigma exserted beyond anthers at anthesis. |
usually 1 opening per day near sunset; buds erect, with free tips erect or appressed, 0.5–2.5 mm; floral tube 23–28 mm; sepals 5–12 mm; petals yellow, fading orange, broadly obovate or shallowly obcordate, 6–15 mm; filaments 4–12 mm, anthers 3–4 mm, pollen 85–100% fertile; style 27–40 mm, stigma surrounded by anthers at anthesis. |
Capsules | ovoid, 4-angled, somewhat flattened, 3–4 × 1.5–2.3 mm, valves with raised midrib and conspicuous lateral veins; sessile. |
cylindrical, sometimes slightly enlarged toward apex, 25–45 × 2.5–3 mm. |
Seeds | 1, pale yellow, oblanceoloid, 2.4–2.6 × 1–1.5 mm. |
ellipsoid to subglobose, 0.8–1.2 × 0.3–0.5 mm. |
2n | = 14. |
= 14. |
Oenothera glaucifolia |
Oenothera mexicana |
|
Phenology | Flowering May–Oct(–Nov). | Flowering Apr–May. |
Habitat | Rocky prairie slopes and outcrops or bluffs, along streams, roadsides, usuallyon limestone. | Open, sandy sites. |
Elevation | 200–1300 m. (700–4300 ft.) | 30–200 m. (100–700 ft.) |
Distribution |
AR; CO; KS; MO; NE; NM; OK; TX; WY
|
TX |
Discussion | Oenothera glaucifolia is self-incompatible, the flowers diurnal, pollinated primarily by wasps (R. Clinebell, unpubl.), as well as bees, flies, butterflies, and occasionally beetles (summarized by W. L. Wagner et al. 2007). It was collected once in 1988 in Indiana at Miller Woods Visitor Center (Lake County), Dritz 596 (MOR); it seems likely that it was introduced, and has not been collected there since. Stenosiphon virgatus Spach is a superfluous name and pertains here. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Oenothera mexicana is known only from southeastern Texas (Atascosa, Aransas, Bexar, Brooks, Burleson, De Witt, Frio, Gonzales, Kenedy, Medina, Newton, Refugio, San Patricio, Waller, and Washington counties). It is self-compatible and autogamous, but not a PTH species. (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. Gaura > subsect. Stenosiphon | Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Oenothera > subsect. Raimannia |
Sibling taxa | ||
Synonyms | Gaura linifolia, Stenosiphon linifolius | O. laciniata var. mexicana, O. sinuata var. hirsuta, Raimannia mexicana |
Name authority | W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 212. (2007) | Spach: Nouv. Ann. Mus. Hist. Nat. 4: 347. (1836) |
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