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basket evening-primrose, birdcage evening primrose, desert lantern, devil's lantern, dune primrose, hairy evening primrose, lion-in-a-cage

white-stem evening-primrose, whitest evening primrose, whitish evening primrose

Habit Herbs usually winter-annual, sometimes perennial, glabrous, glandular puberulent, strigillose, and/or villous, sometimes more villous distally, hairs sometimes very curly, especially on flower parts; from a taproot or relatively long, fleshy roots. Herbs winter-annual, densely strigillose, also sparsely villous; from a taproot.
Stems

central stem usually erect, usually thickened at base and spongy, branched or unbranched, branches few–several, slender, decumbent to ascending, from base, usually encircling central stem in older plants, 10–40(–100) cm.

ascending to decumbent, 1–several from base, sometimes unbranched, erect or ascending, 5–30 cm.

Leaves

in a basal rosette and cauline, rosette usually well developed (except subsp. howellii), basal 5–25 × 1–5 cm, cauline 4–12(–18) × 0.5–4 cm;

petiole 1.5–8 cm;

blade rhombic-obovate, lanceolate, or oblanceolate, margins subentire, dentate, or pinnatifid.

in a basal rosette and cauline, 1.5–10 × 0.3–2.5 cm;

blade oblanceolate to oblong, margins subentire or coarsely dentate or pinnatifid.

Flowers

1–several opening per day near sunset;

buds nodding, weakly or strongly quadrangular or fluted in distal 1/2, with free tips 0–9 mm;

floral tube 20–40 mm;

sepals (13–)15–35 mm, not spotted;

petals white, fading pink to deep pink, broadly obovate or obcordate, 15–44 mm;

filaments 8–15 mm, anthers 5–14 mm;

style 35–60 mm, stigma exserted beyond anthers at anthesis.

1–3 opening per day near sunset;

buds nodding, weakly quadrangular, without free tips;

floral tube 15–30 mm, mouth glabrous;

sepals 15–30 mm;

petals white, fading pink, usually obcordate, sometimes obovate, (15–)20–35(–40) mm;

filaments 11–17 mm, anthers 6–10 mm;

style 25–50 mm, stigma exserted beyond anthers at anthesis.

Capsules

spreading, straight to curved, becoming somewhat woody in age, cylindrical to slightly 4-angled, widest toward base, tapering from base to apex, (15–)30–80 × 1.5–5 mm;

sessile.

ascending to erect, usually straight, sometimes curved, cylindrical, weakly 4-angled, 20–40 × 3–4 mm, dehiscent 1/2 their length;

sessile.

Seeds

numerous, in 1 row per locule, buff with dark spots or black, narrowly obovoid, 1.5–2.8 mm.

in 2 rows per locule, ellipsoid to subglobose, 0.8–1.5 × 0.5–0.9 mm, surface regularly pitted, pits in longitudinal lines.

2n

= 14.

Oenothera deltoides

Oenothera albicaulis

Phenology Flowering (Feb–)Mar–Jun(–Dec).
Habitat Dry, usually sandy flats and slopes.
Elevation 1000–2300 m. (3300–7500 ft.)
Distribution
from USDA
w United States; nw Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; ID; KS; MT; ND; NE; NM; OK; SD; TX; UT; WY; Mexico (Chihuahua, Sonora)
[WildflowerSearch map]
[BONAP county map]
Discussion

Subspecies 5 (5 in the flora).

Oenothera deltoides is self-incompatible or self-compatible (W. M. Klein 1964; W. L. Wagner et al. 2007; K. E. Theiss et al. 2010).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Oenothera albicaulis is self-incompatible (W. L. Wagner et al. 2007; K. E. Theiss et al. 2010). Oenothera albicaulis has been reported from southern Nevada, but documentation is needed of its occurrence there.

Anogra pinnatifida Spach, Baumannia pinnatifida Spach, Oenothera pinnatifida Nuttall, O. purshiana Steudel, and O. purshii G. Don are illegitimate names that pertain here.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Herbs perennial, from long, fleshy roots; stems not thickened at base, branches erect or ascending, not encircling stems in older plants.
subsp. howellii
1. Herbs annual or short-lived perennial from a taproot; stems usually thickened at base, branches ascending or decumbent, often encircling stems in older plants.
→ 2
2. Flower buds fluted or strongly quadrangular in distal 1/2, without free tips, villous with curly hairs, sometimes glabrous; leaf blade margins sinuate-dentate to pinnatifid; petals 15–25(–30) mm; capsules 15–25(–30) mm.
subsp. piperi
2. Flower buds weakly or strongly quadrangular in distal 1/2, with free tips 0–3 mm, strigillose, sparsely to moderately villous, or glabrous; leaf blade margins sinuate-dentate or subentire, rarely pinnatifid; petals 15–44 mm; capsules 40–80 mm.
→ 3
3. Flower buds with free tips 1–3 mm, quadrangular in distal 1/2; plants strigillose, especially distally.
subsp. ambigua
3. Flower buds with free tips 0–1.5 mm, weakly quadrangular in distal 1/2; plants glabrous, villous, or strigillose.
→ 4
4. Herbs annual, strigillose, sometimes also villous; capsules 2–3.5 mm diam.; flower buds with free tips 0–1.5 mm.
subsp. deltoides
4. Herbs short-lived perennial or some­times annual, glabrous or sparsely villous, rarely also strigillose; capsules 3–5 mm diam.; flower buds without free tips.
subsp. cognata
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Anogra Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Kleinia
Sibling taxa
O. acutissima, O. albicaulis, O. argillicola, O. arida, O. arizonica, O. biennis, O. boquillensis, O. brachycarpa, O. calcicola, O. californica, O. canescens, O. capillifolia, O. cavernae, O. cespitosa, O. cinerea, O. clelandii, O. coloradensis, O. cordata, O. coronopifolia, O. coryi, O. curtiflora, O. curtissii, O. demareei, O. dodgeniana, O. drummondii, O. elata, O. engelmannii, O. falfurriae, O. filiformis, O. filipes, O. flava, O. fruticosa, O. gaura, O. gayleana, O. glaucifolia, O. glazioviana, O. grandiflora, O. grandis, O. harringtonii, O. hartwegii, O. havardii, O. heterophylla, O. hispida, O. howardii, O. humifusa, O. jamesii, O. kunthiana, O. laciniata, O. lavandulifolia, O. lindheimeri, O. linifolia, O. longissima, O. macrocarpa, O. mckelveyae, O. mexicana, O. nealleyi, O. neomexicana, O. nutans, O. nuttallii, O. oakesiana, O. organensis, O. pallida, O. parviflora, O. patriciae, O. perennis, O. pilosella, O. platanorum, O. podocarpa, O. primiveris, O. psammophila, O. pubescens, O. rhombipetala, O. riparia, O. rosea, O. serrulata, O. sessilis, O. simulans, O. sinuosa, O. spachiana, O. speciosa, O. stricta, O. suffrutescens, O. suffulta, O. tetraptera, O. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
O. acutissima, O. argillicola, O. arida, O. arizonica, O. biennis, O. boquillensis, O. brachycarpa, O. calcicola, O. californica, O. canescens, O. capillifolia, O. cavernae, O. cespitosa, O. cinerea, O. clelandii, O. coloradensis, O. cordata, O. coronopifolia, O. coryi, O. curtiflora, O. curtissii, O. deltoides, O. demareei, O. dodgeniana, O. drummondii, O. elata, O. engelmannii, O. falfurriae, O. filiformis, O. filipes, O. flava, O. fruticosa, O. gaura, O. gayleana, O. glaucifolia, O. glazioviana, O. grandiflora, O. grandis, O. harringtonii, O. hartwegii, O. havardii, O. heterophylla, O. hispida, O. howardii, O. humifusa, O. jamesii, O. kunthiana, O. laciniata, O. lavandulifolia, O. lindheimeri, O. linifolia, O. longissima, O. macrocarpa, O. mckelveyae, O. mexicana, O. nealleyi, O. neomexicana, O. nutans, O. nuttallii, O. oakesiana, O. organensis, O. pallida, O. parviflora, O. patriciae, O. perennis, O. pilosella, O. platanorum, O. podocarpa, O. primiveris, O. psammophila, O. pubescens, O. rhombipetala, O. riparia, O. rosea, O. serrulata, O. sessilis, O. simulans, O. sinuosa, O. spachiana, O. speciosa, O. stricta, O. suffrutescens, O. suffulta, O. tetraptera, O. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
Subordinate taxa
O. deltoides subsp. ambigua, O. deltoides subsp. cognata, O. deltoides subsp. deltoides, O. deltoides subsp. howellii, O. deltoides subsp. piperi
Synonyms Anogra deltoides Anogra albicaulis, A. bradburiana, A. buffumii, A. confusa, A. ctenophylla, A. perplexa, O. albicaulis var. xanthosperma, O. ctenophylla, O. sinuata var. bicolor
Name authority Torrey & Frémont in J. C. Frémont: Rep. Exped. Rocky Mts., 315. (1845) Pursh: Fl. Amer. Sept. 2: 733. (1813)
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