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lizard-tail, small-flower bee-blossom, small-flower gaura, velvet weed

Fendler evening primrose, Hartweg's sundrops

Habit Herbs annual, strigillose, glandular puberulent, and long-villous; from heavy taproot, 2–4 cm diam. Herbs perennial, sometimes suffrutescent, strigillose, glandular puberulent, glabrous, hirtellous, or short-pilose; from a stout taproot.
Stems

erect, unbranched or many-branched distally, (20–)30–200(–300) cm.

1–many, erect to ascending, unbranched to densely branched, 4–60 cm.

Leaves

in a basal rosette and cauline, basal 4–15 × 1.5–3 cm, petiole 0–1.8 cm, blade broadly oblanceolate, margins sinuate-dentate to dentate;

cauline 2–13 × 0.5–5 cm, petiole 0–2 cm, blade narrowly elliptic to narrowly ovate, margins sinuate-dentate to dentate.

0.3–6.5 × 0.04–1.2 cm, sometimes fascicles of small leaves 0.1–1.5 cm present in non-flowering axils;

petiole 0–0.2 cm;

blade elliptic, lanceolate, linear, or filiform to ovate or oblanceolate, usually not much reduced distally, proximalmost leaves sometimes obovate to spatulate, base attenuate to obtuse, truncate, or subcordate, sometimes clasping, margins entire or serrate, often undulate, apex acute.

Inflorescences

relatively long, dense.

Flowers

4-merous, nearly actinomorphic, opening near sunset;

floral tube 1.5–5 mm;

sepals 2–3.5 mm;

petals white, fading pale to dark pink, slightly unequal, oblong-obovate to elliptic-oblanceolate, 1.5–3 mm, abruptly clawed;

filaments 1.5–3 mm, anthers 0.5–1 mm, pollen 85–100% fertile;

style 3–9 mm, stigma surrounded by anthers at anthesis.

usually 1 per stem opening per day in afternoon or near sunset;

buds with free tips 0.5–6 mm;

floral tube 16–50(–60) mm, funnelform in distal 1/2 or less;

sepals 7–28 mm;

petals yellow, fading pale pinkish or pale purple, 10–35 mm;

filaments 4–13 mm, anthers 5–13 mm, pollen 85–100% fertile;

style 25–65(–75) mm, stigma yellow, quadrangular, usually exserted beyond anthers.

Capsules

fusiform, terete, weakly angled in distal 1/3, angles becoming broad and rounded in proximal part, 5–11 × 1.5–3 mm, tapering abruptly toward base;

sessile.

6–40 × 2–4 mm, hard, promptly dehiscent throughout their length.

Seeds

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

obovoid, 1–2.5 mm.

2n

= 14.

= 14, 28.

Oenothera curtiflora

Oenothera hartwegii

Phenology Flowering (Feb–)Apr–Oct.
Habitat Rocky prairie slopes, woodlands, along streams, roadsides, disturbed areas.
Elevation 10–2800 m. (0–9200 ft.)
Distribution
from FNA
AL; AR; AZ; CA; CO; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; MN; MO; MT; NE; NM; NV; OK; OR; SC; SD; TN; TX; UT; VA; WA; WY; Mexico (Baja California, Chihuahua, Coahuila, Durango, Nuevo León, Sinaloa, Zacatecas) [Introduced in South America (Argentina), Asia (China, Japan), Australia]
[WildflowerSearch map]
[BONAP county map]
from USDA
c United States; sw United States; n Mexico
[WildflowerSearch map]
[BONAP county map]
Discussion

Oenothera curtiflora is self-compatible and autogamous (P. H. Raven and D. P. Gregory 1972[1973]). Sometimes it is apparently a biennial. The species is native to grassland regions and open areas across much of interior North America. The full extent of its indigenous range is not clear and collections from the eastern half of the United States (Alabama, Florida, Georgia, Indiana, Massachusetts, and Tennessee) and California may be more recent introductions. Gaura mollis Nuttall ex Torrey 1827 is an isonym of G. mollis E. James 1822, a suppressed name.

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

Subspecies 5 (5 in the flora).

Oenothera hartwegii consists of five intergrading subspecies, which are generally locally common on rocky, sandy, gypsum, or limestone soil in arid to relatively mesic open areas, in southeastern Colorado, southwestern Kansas, western Oklahoma, Texas (except eastern part), New Mexico, southeastern and east-central Arizona, and in Mexico from Chihuahua, northern Coahuila, and northwestern Tamaulipas south to Aguascalientes. H. F. Towner (1977) found that O. hartwegii is self-incompatible and usually vespertine; two of the subspecies (filifolia and maccartii) open early in the afternoon and are pollinated both day and evening.

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

Key
1. Leaves (except proximalmost): blade base truncate or subcordate and clasping; plants densely pubescent with mixture of hair types, but always short-pilose and usually also hirtellous, sometimes also strigillose, especially on leaves, or glandular puberulent distally.
subsp. pubescens
1. Leaves: blade base attenuate or obtuse; plants glabrous, sparsely strigillose, or glandular puberulent.
→ 2
2. Plants usually glabrous throughout, sometimes glandular puberulent on distal parts, especially on ovary.
subsp. fendleri
2. Plants strigillose and/or glandular puberulent, especially on distal parts.
→ 3
3. Plants glandular puberulent throughout, more densely so on distal parts, sometimes also sparsely strigillose on ovary and leaves; leaf blades filiform to narrowly lanceolate.
subsp. filifolia
3. Plants usually strigillose, rarely glandular puberulent; leaf blade narrowly lanceolate to oblanceolate, sometimes linear.
→ 4
4. Leaf blades narrowly lanceolate, sometimes linear, margins entire or shallowly and sparsely serrulate, sometimes undulate; plants sparsely to densely strigillose throughout.
subsp. hartwegii
4. Leaf blades usually narrowly lanceolate to lanceolate or oblanceolate, rarely linear, margins subentire or serrulate, usually crinkled-undulate; plants usually sparsely strigillose, sometimes glandular puberulent.
subsp. maccartii
Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Gaura > subsect. Schizocarya Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Calylophus > subsect. Salpingia
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. 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. 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. 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. hartwegii subsp. fendleri, O. hartwegii subsp. filifolia, O. hartwegii subsp. hartwegii, O. hartwegii subsp. maccartii, O. hartwegii subsp. pubescens
Synonyms Gaura parviflora, G. australis, G. hirsuta, G. micrantha, G. parviflora var. lachnocarpa, Schizocarya micrantha Calylophus hartwegii, Galpinsia hartwegii, Salpingia hartwegii
Name authority W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 211. (2007) Bentham: Pl. Hartw., 5. (1839) — (as hartwegi)
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