Oenothera oakesiana |
Oenothera gaura |
|
---|---|---|
Oakes' evening-primrose |
biennial bee-blossom |
|
Habit | Herbs biennial, densely silky-strigillose, at least proximally, also sparsely villous with long, appressed hairs, sometimes also villous with spreading, pustulate hairs and/or glandular puberulent distally. | Herbs usually robust winter-annual, sometimes biennial, usually moderately to densely villous, rarely short-hirtellous, also glandular puberulent; from fleshy taproot. |
Stems | erect to decumbent, green or flushed with red on proximal parts or throughout, unbranched or bushy and branched from base, with side branches arising obliquely or arcuately from rosette, 10–60 cm. |
usually well-branched distal to base, 50–180 cm. |
Leaves | in a basal rosette and cauline, basal 8–30 × 0.5–3 cm, cauline 3.5–20 ×0.5–2.7 cm; blade grayish green to dull green, very narrowly oblanceolate to narrowly oblanceolate or narrowly elliptic, margins flat, subentire or remotely dentate, teeth sometimes blunt, sometimes sinuate-dentate proximally; bracts persistent. |
in a basal rosette and cauline, basal 8–20 × 1.5–3 cm, blade oblanceolate, margins irregularly toothed to lobed; cauline 1.5–12 × 0.5–3 cm, blade narrowly elliptic to elliptic or lanceolate, margins subentire or undulate-denticulate. |
Inflorescences | usually recurved with ascending tip distally, rarely suberect, unbranched. |
|
Flowers | opening near sunset; buds erect, 3–5 mm diam., with free tips subterminal, spreading to erect, 2.5–4 mm; floral tube 15–40 mm; sepals green to yellow, flushed with red and dark red flecked or red-striped, 9–17 mm; petals yellow to pale yellow, fading yellowish white to pale yellowish orange, very broadly obcordate, 7–20 mm; filaments 6–15 mm, anthers 3–7 mm, pollen ca. 50% fertile; style 20–45 mm, stigma surrounded by anthers at anthesis. |
4-merous, zygomorphic, opening at sunset; floral tube 6–13 mm; sepals 5–13 mm; petals white, fading pink to red, narrowly elliptic-obovate, 6–12 mm; filaments 5–10 mm, anthers 2–4 mm, pollen 35–65% fertile; style 12–15 mm, stigma surrounded by anthers. |
Capsules | erect or slightly spreading, usually rusty brown when dry, narrowly lanceoloid to lanceoloid, 15–40 × 4–8 mm, free tips of valves 0.5 mm. |
ellipsoid, 4-angled, 5–9 × 2–3 mm; sessile. |
Seeds | 1.1–1.2 ×0.8–1 mm. |
3–6, light to reddish brown, 2–2.5 × 1–1.3 mm. |
2n | = 14. |
= 14. |
Oenothera oakesiana |
Oenothera gaura |
|
Phenology | Flowering Jun–Aug. | Flowering Jun–Oct. |
Habitat | Sandy coastal meadows and dunes, gravelly or rocky sites along rivers, disturbed sites, roadsides. | Open woods, fields, along streams, disturbed sites, ditch banks, roadsides, railway embankments. |
Elevation | 0–50(–500) m. (0–200(–1600) ft.) | 100–600 m. (300–2000 ft.) |
Distribution |
CT; DC; DE; IL; IN; MA; MD; ME; MI; MN; NH; NJ; NY; OH; PA; RI; VA; VT; WI; MB; NB; NF; NS; ON; PE; QC [Introduced in Europe, Asia]
|
CT; DC; DE; IA; IL; IN; KY; MA; MD; MI; MN; NC; NJ; NY; OH; PA; TN; VA; VT; WI; WV; ON; QC
|
Discussion | Oenothera oakesiana is a PTH species and 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 IV and a AC genome composition. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Oenothera gaura is a PTH species and forms a ring of 14 chromosomes in meiosis. It is self-compatible and autogamous (P. H. Raven and D. P. Gregory 1972[1973]), and may have been derived from O. filiformis. (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. Oenothera | Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Gaura > subsect. Gaura |
Sibling taxa | ||
Synonyms | O. biennis var. oakesiana, O. ammophila, O. ammophiloides, O. ammophiloides var. angustifolia, O. ammophiloides var. laurensis, O. atrovirens var. ostreae, O. canovirens var. cymatilis, O. cruciata var. stenopetala, O. cymatilis, O. deflexa var. bracteata, O. disjuncta, O. eriensis, O. eriensis var. niagarensis, O. eriensis var. repandodentata, O. germanica, O. insignis, O. laevigata var. rubripunctata, O. leucophylla, O. litorea, O. magdalena, O. millersii, O. muricata var. parviflora, O. niagarensis, O. nobska, O. oakesiana var. nobska, O. oakesiana var. tidestromii, O. ostreae, O. parviflora var. oakesiana, O. perangusta, O. perangusta var. rubricalyx, O. repandodentata, O. rubescens, O. stenopetala, O. tidestromii, Onagra oakesiana | Gaura biennis |
Name authority | (A. Gray) J. W. Robbins ex S. Watson & J. M. Coulter in A. Gray et al.: Manual ed. 6, 190. (1890) | W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 212. (2007) |
Web links |