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fourpoint evening primrose

plains beeblossom

Habit Herbs biennial, densely to sparsely strigillose, sometimes also sparsely glandular puberulent distally. Herbs annual, villous proximally, sparsely villous along leaf veins and on margins, usually glabrate or, sometimes, strigillose distally; from taproot.
Stems

sometimes with lateral branches arising obliquely from rosette, 30–100(–150) cm.

usually well-branched from base and distally, rarely unbranched, 15–65(–85) cm.

Leaves

in a basal rosette and cauline, basal 6–20 × 0.6–2 cm, cauline 3–15 × 0.8–2.5 cm;

blade narrowly oblanceolate, gradually narrowly elliptic to narrowly lanceolate, oblanceolate, or ovate distally, margins lobed to remotely dentate or subentire;

bracts slightly longer than capsule they subtend.

in a basal rosette and cauline, basal 6–9.5 × 1–2 cm, blade lyrate;

cauline 1–7 × 0.1–2.3 cm, blade narrowly lanceolate to oblanceolate, margins shallowly sinuate-denticulate to subentire.

Inflorescences

dense, usually without lateral branches, mature buds usually not overtopping spike apex.

Flowers

2–several per spike opening per day near sunset;

buds erect, with free tips erect, 0.5–3 mm;

floral tube slightly curved upward to ± straight, 30–45 mm;

sepals 15–30 mm;

petals yellow, broadly elliptic to rhombic-elliptic, 15–35 mm;

filaments 13–25 mm, anthers 3–8 mm, pollen 85–100% fertile;

style 25–50 mm, stigma exserted beyond anthers at anthesis.

(3- or)4-merous, zygomorphic, opening at sunset;

floral tube 6–12 mm;

sepals 10–15 mm;

petals white, fading pink to purple, elliptic-obovate, 8–13 mm;

filaments 5–8 mm, anthers 2–4 mm, pollen 90–100% fertile;

style 15–24 mm, stigma exserted beyond anthers at anthesis.

Capsules

narrowly lanceoloid, 13–25 × 2.5–3 mm.

ellipsoid, narrowly (3- or)4-winged, deeply furrowed between wings, 6–10 × 2–3 mm, with or without prominent lower corners, narrowed to a stipe 0–1 mm;

sessile.

Seeds

brown, sometimes flecked with dark red spots, ellipsoid, 1–1.7 × 0.4–0.7 mm.

3 or 4, yellowish to reddish brown, 2–3 × 1–1.5 mm.

2n

= 14.

= 14.

Oenothera rhombipetala

Oenothera patriciae

Phenology Flowering May–Oct. Flowering Feb–Jun.
Habitat Fields, prairies, sandy soil. Open, sandy sites.
Elevation 60–600(–1300) m. (200–2000(–4300) ft.) 0–300 m. (0–1000 ft.)
Distribution
from FNA
AR; CO; IL; KS; MI; MN; MO; NE; NM; OK; SD; TX; WI
[WildflowerSearch map]
[BONAP county map]
from FNA
LA; MS; OK; TX
[BONAP county map]
Discussion

Oenothera rhombipetala is primarily a central plains species that has scattered localities in the Midwest to Illinois, Michigan, and Wisconsin, and barely entering the easternmost parts of Colorado and New Mexico.

Oenothera rhombipetala had a broader delimitation (P. A. Munz 1965) until W. Dietrich and W. L. Wagner (1988) divided it into three species (O. clelandii, O. curtissii, and O. rhombipetala), with both of the split-off species being PTH. Evidence gathered by Dietrich and Wagner showed that these PTH species are geographically separated populations of small-flowered plants, and although they are very close morphologically, their distributions and morphological differences suggest that they were each derived independently from O. rhombipetala. Oenothera rhombipetala is self-incompatible.

Oenothera pyramidalis H. Léveillé is a superfluous name and pertains here.

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

Oenothera patriciae is known from Acadia Parish, Louisiana, Amite County, Mississippi, Bryan and Love counties, Oklahoma, and eastern Texas.

Reports of Oenothera patriciae near Tulsa, Oklahoma, and at the single locations in Arkansas and Mississippi may represent introductions. P. H. Raven and D. P. Gregory (1972[1973]) determined O. patriciae to be self-compatible, but primarily outcrossing.

(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. Candela Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Gaura > subsect. Gaura
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. parviflora, O. patriciae, O. perennis, O. pilosella, O. platanorum, O. podocarpa, O. primiveris, O. psammophila, O. pubescens, 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. 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. heterophylla var. rhombipetala, O. leona, Raimannia rhombipetala Gaura brachycarpa, G. hexandra var. coryi, G. tripetala var. coryi
Name authority Nuttall ex Torrey & A. Gray: Fl. N. Amer. 1: 493. (1840) W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 213. (2007)
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