Oenothera humifusa |
Oenothera capillifolia |
|||||
---|---|---|---|---|---|---|
seabeach evening-primrose |
|
|||||
Habit | Herbs annual or short-lived perennial, densely strigillose, sometimes also villous, also becoming glandular puberulent distally. | Herbs perennial (short-lived or, sometimes, suffrutescent) or annual, glabrous or strigillose; from a stout taproot. | ||||
Stems | erect to decumbent, much branched, 10–50(–90) cm. |
1–many, weakly decumbent to ascending or erect, unbranched to moderately branched, (10–)25–80 cm. |
||||
Leaves | in a basal rosette and cauline, basal 4–8 × 0.7–1 cm, cauline 1–7 × 0.3–1.5 cm; blade usually grayish green, narrowly oblong to narrowly elliptic or narrowly obovate, margins remotely shallowly dentate to subentire; bracts spreading, flat. |
1–9 × (0.1–)0.3–1 cm, sometimes fascicles of small leaves to 2 cm present in non-flowering axils; petiole 0–0.6 cm; blade linear to narrowly lanceolate or oblanceolate, often folded lengthwise, usually not much reduced distally, proximalmost leaves sometimes spatulate, base attenuate, margins subentire or serrulate or spinulose-serrate, apex acute. |
||||
Flowers | usually 1 opening per day near sunset; buds erect, with free tips erect and appressed or slightly spreading, 0.5–2 mm; floral tube 15–35 mm; sepals3–11 mm; petals yellow, very broadly obovate or obcordate, 4.5–16 mm; filaments 4–11 mm, anthers 2–5.5 mm, pollen ca. 50% fertile; style 23–45 mm, stigma surrounded by anthers at anthesis. |
opening at sunrise; buds with free tips 0–4 mm; floral tube 5–20 mm; sepals 4–12 mm, midribs keeled; petals yellow, fading orangish to purplish, 6–25 mm; antisepalous filaments 2–8 mm, antipetalous filaments 1–4 mm, anthers 2–7 mm, pollen 90–100% fertile; style 9–30 mm, stigma sometimes blue-black, discoid to quadrangular, exserted beyond anthers. |
||||
Capsules | cylindrical, sometimes slightly enlarged toward apex, 15–45 × 2–3 mm. |
10–35 × 1–2 mm, hard, dehiscent 1/2 their length, often tardily dehiscent throughout their length. |
||||
Seeds | usually ellipsoid to broadly ellipsoid, rarely subglobose, 1–2 × 0.5–0.9 mm. |
obovoid, 1–1.8 mm, sharply angled, apex truncate. |
||||
2n | = 14. |
|||||
Oenothera humifusa |
Oenothera capillifolia |
|||||
Phenology | Flowering Apr–Nov. | |||||
Habitat | Dunes, open sandy places along or near Atlantic coast. | |||||
Elevation | 0–10 m. (0–0 ft.) | |||||
Distribution |
AL; DE; FL; GA; LA; MD; MS; NC; NJ; PA; SC; VA; Dunes; open sandy places along or near Atlantic coast; West Indies (Cuba); Bermuda
|
c United States; sc United States; n Mexico |
||||
Discussion | Oenothera humifusa is a PTH species and forms a ring of 14 chromosomes in meiosis, and is self-compatible and autogamous (W. Dietrich and W. L. Wagner 1988). The inland collection from Iredell County, North Carolina, presumably represents an introduction. There are two geographically separated morphological forms of O. humifusa. Plants of one form are somewhat decumbent, with subentire cauline leaves and bracts; this form occurs in the southern part of the range. The other form is more upright, with more deeply divided leaves; it occurs from North Carolina northward. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Subspecies 2 (2 in the flora). Oenothera capillifolia is self-incompatible (H. F. Towner 1977). Oenothera berlandieri (Spach) Steudel 1841, not D. Dietrich 1840, is superfluous and cannot be used in Oenothera when transferred from Calylophus, and pertains here. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||
Key |
|
|||||
Source | FNA vol. 10. | FNA vol. 10. | ||||
Parent taxa | Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Oenothera > subsect. Raimannia | Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Calylophus > subsect. Calylophus | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | O. niveifolia, O. sinuata var. humifusa, Raimannia humifusa | Meriolix capillifolia | ||||
Name authority | Nuttall: Gen. N. Amer. Pl. 1: 245. (1818) | Scheele: Linnaea 21: 576. (1848) | ||||
Web links |