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

beakpod evening primrose, spotted 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 low, forming clumps 10–50 cm diam., densely strigillose throughout; from a taproot, lateral roots producing adventitious shoots.
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.

many-branched from base, leafy, (10–)15–25(–38) 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.

cauline, (0.3–)0.6–1.5(–2.5) × (0.05–)0.15–0.4(–0.6) cm, fascicles of small leaves 0.2–0.6 cm often present in non-flowering axils;

petiole 0–0.1 cm;

blade lanceolate to linear, base cuneate, apex acute.

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.

several opening per day near sunset;

buds usually without free tips, rarely free tips 0.2–0.3 mm;

sepals (7–)8–12 mm;

petals pink, rarely white, streaked or flecked with red, fading bright purple, (8–)10–17 mm;

filaments 6–8 mm, anthers often with red longitudinal stripe, 3–6 mm;

style (16–)22–27 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.

woody, ovoid, narrowly winged, wings 0.8–1.5 mm wide, (7–)9–12(–14) × 2–4 mm (excluding wings), abruptly constricted to a conspicuous, sterile beak, (2–)3–4.5 mm, indehiscent;

sessile.

Seeds

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

asymmetrically cuneiform or oblanceoloid, 1.2–1.5 × 0.4–0.5 mm.

2n

= 14.

Oenothera deltoides

Oenothera canescens

Phenology Flowering May–Aug.
Habitat Prairie depressions, playas, margins of ditches, temporary wet areas.
Elevation (400–)700–1800 m. ((1300–)2300–5900 ft.)
Distribution
from USDA
w United States; nw Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
CO; KS; NE; NM; OK; TX; WY
[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 canescens is restricted to prairie depressions, playas, ditch margins, and other places of temporary water in the High Plains of the western United States from Goshen County, Wyoming, southeast to Hayes County, Nebraska, south through eastern Colorado, the eastern tier of counties in New Mexico, western Kansas, and to Garza and Dawson counties in the Texas Panhandle; also disjunct populations from Chautauqua, Sedgwick, and Stafford counties, Kansas.

The illegitimate names Gaurella guttulata (Geyer ex Hooker) Small, G. canescens (Torrey & Frémont) Cockerell, and Gauropsis guttulata (Geyer ex Hooker) Cockerell 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. Gauropsis
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. albicaulis, O. argillicola, O. arida, O. arizonica, O. biennis, O. boquillensis, O. brachycarpa, O. calcicola, O. californica, 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 Gaurella canescens, Megapterium canescens, O. guttulata
Name authority Torrey & Frémont in J. C. Frémont: Rep. Exped. Rocky Mts., 315. (1845) Torrey & Frémont in J. C. Fremont: Rep. Exped. Rocky Mts., 315. (1845)
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