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fragrant evening-primrose, tuft evening-primrose

cave evening-primrose, cavedwelling evening primrose

Habit Herbs perennial, acaulescent or caulescent, usually hirsute or villous, usually also glandular puberulent, or exclusively strigillose, rarely glabrous; from stout taproot, sometimes lateral roots producing adventitious shoots. Herbs winter or spring annual, acaulescent or short-caulescent, glandular puberulent, sometimes also sparsely hirsute; from a taproot.
Stems

(when present), usually ascending or decumbent, unbranched or branched from near base, 0–40 cm.

(when present) 1–several, ascending, usually unbranched, 2–4 cm.

Leaves

1.7–26(–36) × (0.3–)0.5–4.5(–6.5) cm;

petiole (0.2–)1.7–11(–14) cm;

blade usually oblanceolate to rhombic or spatulate, rarely elliptic, obovate, lanceolate, or linear-oblanceolate, margins irregularly sinuate-dentate, serrate, pinnatifid, lobed, or subentire, apex usually acute to rounded, rarely acuminate.

primarily in a basal rosette, sometimes also cauline, (0.5–)2.5–13(–19.5) × (0.2–)0.6–2.3(–2.7) cm;

petiole 0.5–5.2 cm;

blade oblanceolate to elliptic-oblanceolate (in some exceptionally large leaves), margins lyrate-pinnatifid to subentire (in very small ones), apex usually rounded, rarely acute.

Flowers

1–4(–6) per stem opening per day near sunset, with moderate to strong sweet scent with a rubbery background scent;

buds usually erect, rarely recurved (during early development);

floral tube (20–)40–140(–165) mm;

sepals (15–)18–45(–54) mm;

petals white, fading rose or rose pink to dark or deep rose purple, or pink to pale or light rose, or lavender, obovate or obcordate, (16–)20–50(–60) mm;

filaments (6–)10–30(–35) mm, anthers (6–)9–17(–20) mm;

style (45–)60–180(–185) mm, stigma exserted beyond anthers at anthesis.

1–3(–10) per stem opening per day near sunset, without noticeable scent;

buds sometimes ± recurved before anthesis;

floral tube (20–)30–37(–47) mm;

sepals 4.5–12 mm;

petals white, fading pale pink, (6.5–)8–20(–25) mm;

filaments 5.2–7.5(–12) mm, anthers (1.4–)3–4.5(–6) mm;

style (24–)35–45(–56) mm, stigma surrounded by anthers at anthesis.

Capsules

straight, curved, falcate, or sigmoid, usually cylindrical to lanceoloid or ellipsoid, sometimes ovoid, usually obtusely 4-angled, (10–)13–50(–68) × 4–9 mm, tapering to a sterile beak 6–8 mm, valve margins with rows of distinct tubercles to sinuate or nearly smooth ridges, dehiscent 1/3–7/8 their length;

pedicel (0–)1–40(–55) mm.

falcate (especially before maturity), ellipsoid-ovoid to ovoid, obtusely 4-angled, 12–38 × 6–14 mm, tapering to a sterile beak 2–8 mm, dehiscent to 1/2 their length, valve margins with a sinuate ridge or 8–20 nearly distinct tubercles;

pedicel 0–10 mm.

Seeds

numerous in 1 or 2 rows per locule, usually obovoid, oblong, or triangular, rarely suborbicular, 2.1–3.9 × 1–2.6 mm, embryo 1/5–2/3 of seed volume, surface papillose, reticulate or rarely irregularly roughened;

seed collar sealed by a thin membrane, this flat or depressed into raphial cavity, when depressed often splitting, becoming separated from seed collar.

usually numerous, sometimes as few as 5, in 2 adjacent rows per locule, obovoid, 2.5–3.1 × 1.1–1.4 mm, embryo 1/2 of seed volume, surface minutely papillose to reticulate;

seed collar without membrane, producing a large empty cavity, margin irregularly sinuate.

2n

= 14, 28.

= 14.

Oenothera cespitosa

Oenothera cavernae

Phenology Flowering Mar–May.
Habitat Exposed calcareous slopes, crevices in limestone, dolomite, or loose talus, sandy arroyos, sandstone, granitic crevices, volcanic cinders in Mojave Desert or Great Basin scrub communities, rarely in arid juniper woodlands.
Elevation 400–1700 m. (1300–5600 ft.)
Distribution
from USDA
w North America; nw Mexico
[WildflowerSearch map]
from FNA
AZ; CA; NV
[BONAP county map]
Discussion

Subspecies 5 (5 in the flora).

Oenothera cespitosa occurs in a wide array of habitats, from grassland, desert scrub, pinyon-juniper woodland, or Arizona chaparral to montane conifer forests, rarely at timberline, at elevations from (450–)800–3370 m. Oenothera cespitosa is self-incompatible (W. L. Wagner et al. 1985; Wagner 2005).

Pachylophus nuttallii Spach is an illegitimate name that pertains here.

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

Oenothera cavernae is known from the Arrow Canyon, Las Vegas, and Sheep ranges and the low hills near Arden and Sloan in Clark County, Nevada, eastward along the Grand Canyon to the vicinity of Page, Arizona, and perhaps Washington County, Utah and formerly in Glenn Canyon, and more recently collected in eastern San Bernardino County, California (eastern Clark Mountain Range, and the base of range in Ivanpah Valley). W. L. Wagner et al. (1985) determined O. cavernae to be self-compatible and autogamous.

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

Key
1. Plants glabrous.
→ 2
2. Floral tubes (28–)35–60(–85) mm; petals fading rose pink to dark rose purple; capsules falcate or sigmoid, valve margins tuberculate.
subsp. cespitosa
2. Floral tubes (45–)75–110(–153) mm; petals fading pink or rarely pale rose; capsules somewhat curved, valve margins with smooth to irregular, undulate ridges.
subsp. macroglottis
1. Plants hirsute, villous, glandular puberulent, or strigillose.
→ 3
3. Plants strigillose, rarely glandular puberulent; petals fading rose pink to dark rose purple.
subsp. cespitosa
3. Plants hirsute or villous, usually also glandular puberulent, rarely only glandular puberulent; petals fading pink to light or pale rose or lavender-rose, sometimes deep rose purple.
→ 4
4. Stems unbranched to many-branched, sometimes producing dense clumps 5–50 cm diam.; petals fading rose; seed collar sinuate distally.
subsp. crinita
4. Stems unbranched to several-branched, not forming clumps; petals fading rose purple or pink to pale rose or lavender; seed collar various.
→ 5
5. Petals fading rose or sometimes deep rose purple; capsules ellipsoid to lanceoloid-ellipsoid, falcate or sigmoid; pedicels 0.5–1 mm; seed collar membrane depressed and often splitting at maturity, margin conspicuously sinuate throughout.
subsp. crinita
5. Petals fading pink to pale rose or lavender; capsules lanceoloid to cylindrical, straight or somewhat curved; pedicels usually (0–)1–40(–55) mm; seed collar membrane neither depressed nor splitting at maturity, margin not sinuate, sometimes somewhat so distally.
→ 6
6. Capsules oblong-lanceoloid; buds often recurved when young; floral tube (35–)40–70(–80) mm; plants shaggy-villous, sometimes densely so.
subsp. navajoensis
6. Capsules cylindrical to lanceoloid-cylindrical; buds erect; floral tube (41–)75–140-(–165) mm; plants hirsute.
→ 7
7. Capsules somewhat curved, valve margins with nearly smooth to irregular, undulate ridges; leaf blades oblanceolate to spatulate, margins dentate.
subsp. macroglottis
7. Capsules straight, valve margins with minute to conspicuous tubercles, these sometimes coalesced into a sinuate ridge; leaf blades usually oblanceolate to narrowly elliptic, rarely lanceolate, margins usually pinnately lobed to dentate, rarely serrate.
subsp. marginata
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Pachylophus Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Pachylophus
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. 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. 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. 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. tetraptera, O. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
Subordinate taxa
O. cespitosa subsp. cespitosa, O. cespitosa subsp. crinita, O. cespitosa subsp. macroglottis, O. cespitosa subsp. marginata, O. cespitosa subsp. navajoensis
Synonyms Pachylophus cespitosus
Name authority Nuttall: Cat. Pl. Upper Louisiana, no. 53. (1813) Munz: Leafl. W. Bot. 3: 50. (1941)
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