Oenothera curtiflora
Oenothera biennis
lizard-tail, small-flower bee-blossom, small-flower gaura, velvet weed
common evening-primrose, eastern evening primrose, evening star, King's-cureall, small flower evening primrose
erect, unbranched or many-branched distally, (20–)30–200(–300) cm.
erect, green or flushed with red on proximal parts, sometimes inflorescence axis red, unbranched or with side branches obliquely arising from rosette or stem, 30–200 cm.
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.
in a basal rosette and cauline, basal 10–30 × 2–5 cm, cauline 5–22 ×(1–)1.5–5(–6) cm;
blade usually green to pale green, narrowly oblanceolate to oblanceolate, sometimes narrowly elliptic to elliptic distally, margins usually flat, rarely undulate, bluntly dentate, teeth widely spaced, sometimes sinuate-dentate proximally or lobed;
bracts persistent.
relatively long, dense.
erect, unbranched or with secondary branches just proximal to main one, internodes in fruit usually shorter than capsule.
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.
opening near sunset;
buds erect, 3.5–6 mm diam., with free tips terminal, erect or spreading, 1.5–3 mm;
floral tube (20–)25–40 mm;
sepals yellowish green, rarely flushed with red or red-striped, 12–22(–28) mm;
petals yellow to pale yellow, fading yellowish white and somewhat translucent, very broadly obcordate, 12–25(–30) mm;
filaments 8–15(–20) mm, anthers 3–6(–9) mm, pollen 50% fertile;
style 30–55 mm, stigma surrounded by anthers at anthesis.
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.
erect or slightly spreading, dull green when dry, lanceoloid, 20–40 × 4–6 mm, free tips of valves 0.8–1.5 mm.
3 or 4, reddish brown, 2–3 × 1–1.5 mm.
1–1.2 × 0.6–1.1 mm.
= 14.
= 14.
Oenothera curtiflora
Oenothera biennis
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.)
Oenothera biennis is a PTH species and usually forms a ring of 14 chromosomes or a ring of 12 and 1 bivalent in meiosis, and is self-compatible and autogamous (W. Dietrich et al. 1997). It has plastome II and a BA or AB genome composition across different populations.
W. Dietrich et al. (1997) found that in the western half of the United States, where Oenothera biennis is most likely introduced, there are distinctive series of forms that seemed similar to a phenotype of O. biennis that originated in Europe. The most distinctive morphological characters of this western form are the densely villous stems with pustulate hairs and the intense, often dark red color of the stems and sepals, characters which are not typical for the eastern North America forms of O. biennis. The pustulate pubescence of this form is also a characteristic feature of many O. elata and O. villosa subsp. strigosa forms, suggesting possible past hybridization with them. Crossing studies confirm that one of these taxa was most likely involved, and these studies showed that, like O. biennis, they are all AB and BA genomic combinations. One of the seemingly odd features of this form is its scattered distribution across a wide expanse of western states. A possible explanation is that perhaps O. biennis spread westward during glacial periods, hybridized with AA taxa (O. elata and O. villosa subsp. strigosa), followed by compression during warming periods since. A hypothesis of repeated recent hybridization does not seem likely since more typical eastern forms of O. biennis are not present throughout much of the western states. Oenothera biennis hybridizes with the other species of subsect. Oenothera with which it comes in contact, includingO. grandiflora, O. nutans, O. oakesiana, O. parviflora, O. villosa subsp. strigosa, and O. villosa subsp. villosa.
Oenothera biennis subsp. rubricaulis (Klebahn) Stomps is a later homonym that pertains here.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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WA - Local Web sites: CalFlora, CalPhotos,
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WildflowerSearch
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- Local floras: BC, CA, OR, WA
- Local Web sites: CalFlora, CalPhotos, Flora NW, Go Botany, IL Wildflowers, KS Wildflowers, LA Plants, MD Biodiversity,
MI Flora, MN Wildflowers, MO Plants, PNW Herbaria, Turner Photog. - WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
