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northern evening-primrose, small-flower evening-primrose

fourwing evening-primrose

Habit Herbs biennial, sparsely strigillose, glandular puberulent, and villous with pustulate or non-pustulate hairs, sometimes predominately strigillose proximally or predominately villous with pustulate or non-pustulate hairs distally, glabrous, or some mixture of strigillose, glandular puberulent, or sparsely villous distally, sometimes appearing glabrous to the naked eye. Herbs annual or perennial, strigillose and also hirsute; from a slender taproot.
Stems

erect, green or red on proximal parts or throughout, mostly branched from base or only in distal 1/2, 30–150 cm.

15–50 cm.

Leaves

in a basal rosette and cauline, basal 10–30 × 1–4 cm, cauline 4–18 × 1–3 cm;

blade usually bright green, sometimes pale green distally, white- or red-veined, narrowly oblanceolate, narrowly elliptic to lanceolate, or oblong, margins usually flat, rarely undulate, regularly dentate to remotely denticulate, sometimes teeth widely spaced;

bracts persistent.

2.5–10 × 0.6–2.5 cm;

petiole 0.2–2.2 cm;

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

Inflorescences

erect or ± curved, unbranched or with secondary branches just proximal to main one.

Flowers

opening near sunset;

buds erect, 3–5 mm diam., with free tips subterminal, spreading to erect, 0.5–5 mm;

floral tube 22–40 mm;

sepals green to yellowish green or flushed with red or dark red, sometimes only red-flecked, 7–17 mm;

petals yellow to pale yellow, fading pale yellow to pale yellowish orange, very broadly obcordate, 8–15(–20) mm;

filaments 7–13 mm, anthers 3.5–6 mm, pollen ca. 50% fertile;

style 25–50 mm, stigma surrounded by anthers at anthesis.

1–3 opening per day near sunset;

buds with free tips 0.5–3 mm;

floral tube 10–30 mm;

sepals 20–40 mm;

petals white, fading pink, 20–43 mm;

filaments 12–18 mm, anthers 5–10 mm, pollen 85–100% fertile;

style 19–67 mm, stigma exserted beyond anthers at anthesis.

Capsules

erect or slightly spreading, usually greenish black when dry, narrowly lanceoloid to lanceoloid, 20–40 ×3.5–5 mm, free tips of valves 1–1.5 mm.

broadly clavate or obovoid, 20–51 × 5–7 mm, winged, wings 2–4 mm, valve surface with prominent midrib, proximal stipe 8–45 mm;

sessile.

Seeds

1.1–1.8 × 0.5–1 mm.

narrowly obovoid, 1–1.5 × 0.5–0.7 mm.

2n

= 14.

= 14.

Oenothera parviflora

Oenothera tetraptera

Phenology Flowering Jun–Aug. Flowering Feb–May.
Habitat Open or disturbed, sandy or gravelly sites, roadsides, fallow fields, clearings, riverbanks, along water courses, salt marshes, coastal meadows. Alluvial flats, open areas, sandy soil, weedy sites.
Elevation 0–1700 m. (0–5600 ft.) 10–300[–2000] m. (0–1000[–6600] ft.)
Distribution
from FNA
CT; DC; DE; IA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; ND; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; BC; NB; NF; NS; ON; PE; QC [Introduced in Europe, Asia (ne China, Japan), s Africa, Pacific Islands (New Zealand), Australia]
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; Mexico; Central America; West Indies (Jamaica); n South America [Introduced widely in temperate Europe, Asia, s Africa, Australia]
[WildflowerSearch map]
[BONAP county map]
Discussion

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

Onagra chrysantha Spach 1835, not Michaux 1803, is a superfluous name, as is Onagra chrysantha var. parviflora (Linnaeus) Spach, and both pertain here. O. biformiflora var. cruciata R. R. Gates is an invalid name that pertains here.

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

In the flora area, Oenothera tetraptera is known only from southern Texas. Oenothera tetraptera presumably has become naturalized in South America (Argentina, Bolivia, Colombia, Ecuador, Venezuela), West Indies (Jamaica), Europe, Asia, South Africa, and Australia.

Oenothera candida Dumont Courset is a superfluous name, as is O. candida Bellardi ex Colla, and they both pertain here. The name Hartmannia macrantha Spach is illegitimate and pertains 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. oakesiana, O. organensis, O. pallida, 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. 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. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
Synonyms O. ammophiloidesr. var. flecticaulis, O. ammophiloides var. parva, O. angustifolia, O. angustissima, O. angustissima var. quebecensis, O. apicaborta, O. atrovirens, O. biennis var. cruciata, O. biennis var. parviflora, O. biformiflora, O. cleistantha, O. comosa, O. cruciata, O. cruciata var. sabulonensis, O. deflexa, O. flecticaulis, O. hazeliae, O. hazeliae var. parviflora, O. hazeliae var. subterminalis, O. intermedia, O. laevigata, O. laevigata var. scitula, O. laevigata var. similis, O. novae-scotiae, O. novae-scotiae var. distantifolia, O. novae-scotiae var. intermedia, O. parva, O. parviflora subsp. angustissima, O. parviflora var. angustissima, O. robinsonii, O. rubricapitata, O. scitula, O. subterminalis, O. venosa, Onagra biennis var. cruciata, O. chrysantha var. cruciata, O. cruciata, O. parviflora Hartmannia latiflora, H. tetraptera, O. latiflora, O. tetraptera var. immutabilis, Xylopleurum tetrapterum
Name authority Linnaeus: Syst. Nat. ed. 10, 2: 998. (1759) — (as parviflor) Cavanilles: Icon. 3: 40, plate 279. (1796)
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