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largeflower eveningprimrose, showy evening-primrose

little evening-primrose, perennial evening-primrose, perennial sundrops, small sundrops

Habit Herbs annual, strigillose and sparsely villous, also glandular puberulent distally. Herbs perennial, sparsely to moderately strigillose, glandular puberulent distally; from fibrous roots.
Stems

erect to ascending, often with ascending lateral branches, 15–60(–100) cm.

usually erect to slightly decumbent, unbranched to few-branched distally, (3–)15–30(–75) cm.

Leaves

in a basal rosette and cauline, basal 5–13 × 1–3 cm, cauline 3–10 × 1.5–3.5 cm;

blade green, narrowly oblanceolate to narrowly elliptic, margins lobed or dentate, lobes often dentate;

bracts spreading, flat.

in a basal rosette and cauline, basal 2–4 × 0.2–1.2 cm, petiole (0.2–)0.5–1.2(–2.5) cm, blade oblanceolate to obovate;

cauline 3–7 × 0.2–1.2 cm, petiole 0.1–1 cm, blade oblanceolate to obovate, margins entire or weakly and remotely denticulate.

Inflorescences

nodding, flowers in axils of distalmost few nodes.

Flowers

1–few opening per day near sunset;

buds erect, with free tips terminal, erect or hornlike, 1.5–5 mm;

floral tube 25–45 mm;

sepals 15–30 mm;

petals yellow, very broadly obovate or shallowly obcordate, 25–40 mm;

filaments 12–22 mm, anthers 4–11 mm, pollen 85–100% fertile;

style 40–75 mm, stigma exserted beyond anthers at anthesis.

opening near sunrise, nearly unscented;

buds with free tips to 1 mm, connivent;

floral tube 3–10 mm;

sepals 2–4 mm;

petals bright yellow, fading pale yellow, or orangish yellow to pale pink, 5–10 mm;

filaments 3–4 mm, anthers 1–2 mm, pollen 40–70% fertile;

style 3–4 mm, stigma surrounded by anthers at anthesis.

Capsules

cylindrical, sometimes slightly enlarged toward apex, 25–50 ×2–3 mm.

clavate, 4-angled or narrowly 4-winged, 5–10 × 2–3 mm, stipe 1–2 mm;

sessile.

Seeds

broadly ellipsoid to subglobose, 0.8–1.5 × 0.5–0.9 mm.

0.7–0.8 × 0.2–0.3 mm.

2n

= 14.

= 14.

Oenothera grandis

Oenothera perennis

Phenology Flowering Mar–Sep. Flowering May–Jul(–Aug).
Habitat Open, sandy sites. Fields, open woods, boggy areas.
Elevation 0–1500(–2200) m. (0–4900(–7200) ft.) (0–)150–900(–1400) m. ((0–)500–3000(–4600) ft.)
Distribution
from FNA
AL; AR; CO; CT; FL; IL; IN; KS; LA; MD; MI; MO; NC; NE; NJ; NM; TX; Mexico (Tamaulipas)
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; DC; DE; IA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; NE; NH; NY; OH; PA; RI; SC; TN; VA; VT; WI; WV; BC; MB; NB; NF; NS; ON; PE; QC; SPM
[WildflowerSearch map]
[BONAP county map]
Discussion

Oenothera grandis is probably native to eastern New Mexico and Colorado, Arkansas, Kansas, Louisiana, Missouri, Nebraska, Oklahoma, and Texas, and northeastern Tamaulipas, Mexico. Scattered collections made in other states probably represent introductions (W. Dietrich and W. L. Wagner 1988).

Oenothera grandis is self-incompatible (W. Dietrich and W. L. Wagner 1988).

Oenothera laciniata Hill var. occidentalis Small and O. laciniata var. grandis Britton are illegitimate superfluous names based on O. sinuata Linnaeus var. grandiflora S. Watson and pertain here.

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

Oenothera perennis, a PTH species that forms a ring of 14 chromosomes in meiosis, is self-compatible and autogamous (G. B. Straley 1977). It is disjunct in Nebraska from the rest of its range in eastern North America, occurring in Garfield, Holt, and Rock counties (R. Kaul, pers. comm.). It is introduced in British Columbia.

Oenotherapumila Linnaeus is an illegitimate substitution based on O. perennis Linnaeus, while Kneiffia michauxii Spach is an illegitimate substitution based O. pumila, as is K. pumila Spach, and the three pertain here.

(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. Oenothera > subsect. Raimannia Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Kneiffia
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. 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. 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. 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. 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
Synonyms O. laciniata var. grandiflora, O. sinuata var. grandiflora, Raimannia grandis Kneiffia chrysantha, K. depauperata, K. perennis, O. chrysantha, O. perennis var. rectipilis, O. pumila var. chrysantha, O. pumila var. minima, O. pumila var. pusilla, O. pumila var. rectipilis, O. pusilla
Name authority Smyth: Trans. Kansas Acad. Sci. 16: 160. (1899) Linnaeus: Syst. Nat. ed. 10, 2: 998. (1759)
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