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Photo is of parent taxon

fragrant evening-primrose

Photo is of parent taxon
Habit Herbs caulescent or acaulescent, usually moderately to densely hirsute and glandular puberulent, rarely exclusively glandular puberulent. Herbs acaulescent or short-caulescent, hirsute and glandular puberulent, or glabrous.
Stems

usually unbranched, rarely with 1–several branches from near base, 10–40 cm.

(if present), usually unbranched, rarely with 1–several short laterals, 4–8 cm.

Leaves

(2.8–)10–26(–36) × (0.6–)1–3(–4.5) cm;

petiole (3–)4–11(–14) cm;

blade usually oblanceolate to narrowly elliptic, rarely lanceolate, margins coarsely and irregularly pinnately lobed to dentate or, rarely, serrate.

(6.8–)9.5–23(–32) × (1.3–)2.4–4.5(–6.5) cm;

petiole (3–)4–11(–14) cm;

blade oblanceolate to spatulate, margins often undulate, usually regularly to irregularly dentate, rarely coarsely and irregularly pinnately lobed.

Flowers

floral tube (41–)80–140(–165) mm;

sepals (22–)34–45(–54) mm;

petals fading pink to lavender, (24–)35–50(–60) mm;

filaments (16–)20–30(–35) mm, anthers (10–)12–17(–20) mm;

style (78–)100–150(–185) mm.

floral tube (45–)75–110(–153) mm;

sepals (22–)30–45(–50) mm;

petals fading pink to pale rose, (21–)35–43(–50) mm;

filaments (16–)19–28(–35) mm, anthers (10–)12–17 mm;

style 85–180 mm.

Capsules

straight, cylindrical to, sometimes, lanceoloid-cylindrical, slightly asymmetrical, (21–)25–50(–68) × 6–8 mm, valve margins with minute to conspicuous tubercles, these sometimes coalesced into a sinuate ridge;

pedicel (0–)1–40(–55) mm.

somewhat curved, lanceoloid-cylindrical to cylindrical, symmetrical throughout, sometimes slightly flattened on one side at base, (17–)25–45(–56) × 5–8 mm, valve margins with conspicuous, nearly smooth to irregular undulate ridge;

pedicel 2–7 mm.

Seeds

usually narrowly to broadly obovoid, rarely suborbicular, 2.2–3.4 × 1.1–2.6 mm, embryo 1/5–1/2 of seed volume, surface appearing longitudinally striate, reticulate under magnification;

seed collar large, usually appearing inflated, sealed by a flat membrane which is often slightly depressed into seed collar cavity, margin entire or obscurely sinuate distally.

narrowly obovoid, 2.5–3 × 1–1.4 mm, embryo 1/2 of seed volume, surface minutely papillose to reticulate;

seed collar forming narrow slit above raphe with a slightly sunken membrane, margin entire or obscurely sinuate distally.

2n

= 14.

= 14, 28.

Oenothera cespitosa subsp. marginata

Oenothera cespitosa subsp. macroglottis

Phenology Flowering Mar–Aug. Flowering May–Jul(–Sep).
Habitat Rocky slopes, cracks in rocks, talus, along gravelly creek beds and arroyos, roadcuts in loose to somewhat compacted soil derived from granite, sandstone, limestone, volcanic cinder, rarely shale, mostly in foothill communities of pinyon-juniper woodlands, big sagebrush scrub, chaparral, grass­lands, openings in ponderosa pine forests. Open, igneous rocky slopes, talus, roadcuts, open or shaded and sandy or gravelly sites along streams, rarely on shale, in upper pinyon-juniper woodlands, Gambel oak scrub, ponderosa pine forests, ponderosa pine-Douglas fir forests, spruce-fir-lodgepole pine forests.
Elevation (400–)1200–2300(–3100) m. ((1300–)3900–7500(–10200) ft.) 2000–3100 m. (6600–10200 ft.)
Distribution
from FNA
AZ; CA; CO; ID; NM; NV; OR; TX; UT; WA; WY; Mexico (Chihuahua, Sonora)
from FNA
CO; NM; UT; WY
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Pachylophus > Oenothera cespitosa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Pachylophus > Oenothera cespitosa
Sibling taxa
O. cespitosa subsp. cespitosa, O. cespitosa subsp. crinita, O. cespitosa subsp. macroglottis, O. cespitosa subsp. navajoensis
O. cespitosa subsp. cespitosa, O. cespitosa subsp. crinita, O. cespitosa subsp. marginata, O. cespitosa subsp. navajoensis
Synonyms O. marginata, Anogra longiflora, O. cespitosa subsp. eximia, O. cespitosa var. eximia, O. cespitosa var. longiflora, O. cespitosa var. marginata, O. eximia, O. idahoensis, Pachylophus cylindrocarpus, P. exiguus, P. eximius, P. longiflorus, P. marginatus, P. prolatus Pachylophus macroglottis, O. cespitosa var. macroglottis, P. hirsutus
Name authority (Nuttall ex Hooker & Arnott) Munz in N. L. Britton et al.: N. Amer. Fl., ser. 2, 5: 101. (1965) — (as caespitosa) (Rydberg) W. L. Wagner, Stockhouse & W. M. Klein: Ann. Missouri Bot. Gard. 70: 195. (1983) — (as caespitosa)
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