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beakpod evening primrose, spotted evening-primrose

evening primrose, Hooker's evening-primrose, western evening primrose

Habit Herbs low, forming clumps 10–50 cm diam., densely strigillose throughout; from a taproot, lateral roots producing adventitious shoots. Herbs biennial or short-lived perennial, densely strigillose and either sparsely or moderately villous, with appressed or spreading hairs (sometimes with red-pustulate bases), distally sometimes also glandular puberulent.
Stems

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

erect, green, flushed with red proximally or red throughout, unbranched or branches obliquely arising from rosette and secondary branches arising from main stem, 30–250 cm.

Leaves

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.

in a basal rosette and cauline, basal 10–43 × 1.2–4(–6) cm, cauline 4–25 × 1–2.5(–4) cm;

blade dull green to grayish green, rarely red, narrowly oblanceolate or oblanceolate to narrowly elliptic or narrowly lanceolate, margins usually flat, rarely undulate, bluntly dentate or subentire, teeth sometimes widely spaced, proximal blades sometimes sinuate-dentate toward base;

bracts persistent.

Inflorescences

erect, unbranched.

Flowers

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.

opening near sunset;

buds erect, 6–10 mm diam., with free tips terminal, erect, 1–7 mm;

floral tube (20–)30–45(–50) mm;

sepals yellowish green, red-striped or strongly flushed with red, 27–50 mm;

petals yellow to pale yellow, fading orange or pale yellow, very broadly obcordate, (25–)30–47(–55) mm;

filaments 17–25 mm, anthers 8–23 mm, pollen 90–100% fertile;

style 50–90 mm, stigma exserted beyond anthers at anthesis.

Capsules

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.

erect or slightly spreading, dull green or gray-green when dry, narrowly lanceoloid, 20–65 × 4–7 mm, free tips of valves 0.5–2.5 mm.

Seeds

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

1–1.9 × 0.6–1.2 mm.

2n

= 14.

Oenothera canescens

Oenothera elata

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 FNA
CO; KS; NE; NM; OK; TX; WY
[WildflowerSearch map]
[BONAP county map]
from USDA
w United States; c United States; Mexico; Central America
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Subspecies 3 (2 in the flora).

Subspecies elata differs in anthers 7–12 mm, fewer or no pustulate-based hairs, and generally smaller flowers and habit. It ranges from the highlands of central Mexico, including Guanajuato, Hidalgo, México, Michoacán, Puebla, Querétaro, and Veracruz, south to Guatemala, El Salvador, Costa Rica, and Panama.

Oenothera elata has plastome I and a AA genome composition. Onagra kunthiana Spach is a superfluous name that pertains here.

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

Key
1. Plants strigillose, usually also villous, with appressed or spreading hairs, sometimes these with red-pustulate bases, distally sometimes also glandular puberulent; buds green to yellowish green, red-striped, or sometimes red throughout; anthers 8–15(–20) mm.
subsp. hirsutissima
1. Plants strigillose, also villous with appressed or spreading hairs, usually these with conspicuous red-pustulate bases, also glandular puberulent; buds flushed with red; anthers 12–23 mm.
subsp. hookeri
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Gauropsis Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Oenothera > subsect. Oenothera
Sibling taxa
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
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. deltoides, O. demareei, O. dodgeniana, O. drummondii, 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. elata subsp. hirsutissima, O. elata subsp. hookeri
Synonyms Gaurella canescens, Megapterium canescens, O. guttulata
Name authority Torrey & Frémont in J. C. Fremont: Rep. Exped. Rocky Mts., 315. (1845) Kunth in A. von Humboldt et al.: Nov. Gen. Sp. 6(fol.): 72; 6(qto.): 90. (1823)
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