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Oakes' evening-primrose

Kunth's evening-primrose

Habit Herbs biennial, densely silky-strigillose, at least proximally, also sparsely villous with long, appressed hairs, sometimes also villous with spreading, pustulate hairs and/or glandular puberulent distally. Herbs annual, strigillose and also hirsute; from a slender taproot.
Stems

erect to decumbent, green or flushed with red on proximal parts or throughout, unbranched or bushy and branched from base, with side branches arising obliquely or arcuately from rosette, 10–60 cm.

5–40 cm.

Leaves

in a basal rosette and cauline, basal 8–30 × 0.5–3 cm, cauline 3.5–20 ×0.5–2.7 cm;

blade grayish green to dull green, very narrowly oblanceolate to narrowly oblanceolate or narrowly elliptic, margins flat, subentire or remotely dentate, teeth sometimes blunt, sometimes sinuate-dentate proximally;

bracts persistent.

1–6 × 0.3–3 cm;

petiole 0.1–1.1 cm;

blade usually lanceolate to oblanceolate, sometimes elliptic, margins weakly serrate to sinuate-pinnatifid.

Inflorescences

usually recurved with ascending tip distally, rarely suberect, unbranched.

Flowers

opening near sunset;

buds erect, 3–5 mm diam., with free tips subterminal, spreading to erect, 2.5–4 mm;

floral tube 15–40 mm;

sepals green to yellow, flushed with red and dark red flecked or red-striped, 9–17 mm;

petals yellow to pale yellow, fading yellowish white to pale yellowish orange, very broadly obcordate, 7–20 mm;

filaments 6–15 mm, anthers 3–7 mm, pollen ca. 50% fertile;

style 20–45 mm, stigma surrounded by anthers at anthesis.

1–3 opening per day near sunset;

buds with free tips 0–0.5 mm;

floral tube 5–31 mm;

sepals 10–27 mm;

petals white, fading pink, 8–25 mm;

filaments 6–12 mm, anthers 3–5 mm, pollen 35–65% fertile;

style 12–30 mm, stigma surrounded by anthers at anthesis.

Capsules

erect or slightly spreading, usually rusty brown when dry, narrowly lanceoloid to lanceoloid, 15–40 × 4–8 mm, free tips of valves 0.5 mm.

broadly clavate or obovoid, 7–31 ×3–5 mm, winged, wings 0.5–1.5 mm, valve surface with prominent midrib, proximal stipe 3–17 mm;

sessile.

Seeds

1.1–1.2 ×0.8–1 mm.

narrowly obovoid, 0.9–1.2 × 0.4–0.5 mm.

2n

= 14.

= 14.

Oenothera oakesiana

Oenothera kunthiana

Phenology Flowering Jun–Aug. Flowering Feb–May.
Habitat Sandy coastal meadows and dunes, gravelly or rocky sites along rivers, disturbed sites, roadsides. Alluvial flats, open areas, sandy soil, weedy sites.
Elevation 0–50(–500) m. (0–200(–1600) ft.) 10–1300[–2000] m. (0–4300[–6600] ft.)
Distribution
from FNA
CT; DC; DE; IL; IN; MA; MD; ME; MI; MN; NH; NJ; NY; OH; PA; RI; VA; VT; WI; MB; NB; NF; NS; ON; PE; QC [Introduced in Europe, Asia]
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; Mexico; Central America; n South America [Introduced widely in temperate Europe, Asia, Pacific Islands (Hawaii), Australia]
[WildflowerSearch map]
[BONAP county map]
Discussion

Oenothera oakesiana is a PTH species and forms a ring of 14 chromosomes or a ring of 12 and 1 bivalent in meiosis, and is self-compatible and autogamous (W. Dietrich et al. 1997). It has plastome IV and a AC genome composition.

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

Oenothera kunthiana is a PTH species and forms a ring of 14 chromosomes in meiosis, and is self-compatible and autogamous, common and widespread from sea level to middle elevations in the mountains from southern Texas south throughout Mexico except for Baja California and the tropical lowlands southward to Guatemala, Nicaragua, and Costa Rica; it was once collected in Minas Gerais, Brazil. Oenothera kunthiana was recently found to be naturalized in the Hawaiian Islands.

Oenothera pinnatifida Kunth is a later homonym of O. pinnatifida Nuttall and another later homonym is O. micrantha Walpers, not Hornemann ex Sprengel (1825); they both 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. Oenothera Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Leucocoryne
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. 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. 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. 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
Synonyms O. biennis var. oakesiana, O. ammophila, O. ammophiloides, O. ammophiloides var. angustifolia, O. ammophiloides var. laurensis, O. atrovirens var. ostreae, O. canovirens var. cymatilis, O. cruciata var. stenopetala, O. cymatilis, O. deflexa var. bracteata, O. disjuncta, O. eriensis, O. eriensis var. niagarensis, O. eriensis var. repandodentata, O. germanica, O. insignis, O. laevigata var. rubripunctata, O. leucophylla, O. litorea, O. magdalena, O. millersii, O. muricata var. parviflora, O. niagarensis, O. nobska, O. oakesiana var. nobska, O. oakesiana var. tidestromii, O. ostreae, O. parviflora var. oakesiana, O. perangusta, O. perangusta var. rubricalyx, O. repandodentata, O. rubescens, O. stenopetala, O. tidestromii, Onagra oakesiana Hartmannia kunthiana, H. domingensis, H. parviflora, O. domingensis, O. fissifolia, O. walpersii
Name authority (A. Gray) J. W. Robbins ex S. Watson & J. M. Coulter in A. Gray et al.: Manual ed. 6, 190. (1890) (Spach) Munz: Amer. J. Bot. 19: 759. (1932)
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