Oenothera psammophila |
Oenothera lavandulifolia |
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St. Anthony dunes evening primrose |
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Habit | Herbs perennial, caulescent, glabrous, also with resinous exudate, especially on younger leaves; from woody taproot. | Herbs perennial, densely strigillose throughout, sometimes glandular puberulent distally; from a stout taproot. |
Stems | decumbent, usually branched, 10–30 cm, becoming woody and buried in sand. |
several to many, decumbent to ascending, branched, 4–20(–30) cm. |
Leaves | (6–)8–9(–14.2) × (0.7–)1.5–2(–3.1) cm; petiole 3–9 cm; blade narrowly oblanceolate to oblanceolate, margins usually subentire or repand or remotely dentate, rarely serrate, apex acute. |
0.6–5 × 0.08–0.6 cm, fascicles of small leaves 0.2–1 cm often present in non-flowering axils; petiole 0 cm; blade narrowly lanceolate or narrowly oblanceolate, base attenuate to truncate, sometimes clasping, margins entire or subentire, sometimes revolute, sometimes weakly undulate, apex acute to obtuse. |
Flowers | 1–3 per stem opening per day near sunset, with sweet scent; buds erect; floral tube 42–60 mm; sepals 22–28 mm; petals white, fading rose pink to rose, 23–40 mm; filaments 17–19 mm, anthers 13–16 mm; style 60–72(–88) mm, stigma exserted beyond anthers at anthesis. |
usually 1 per stem opening per day near sunset; buds with free tips 0.3–3 mm; floral tube 25–60 mm, funnelform in distal 1/2 or less; sepals 8–20 mm; petals yellow, fading pale pink or pale purple, 12–28 mm; filaments 6–12 mm, anthers 5–11 mm, pollen 85–100% fertile; style 30–75 mm, stigma yellow, quadrangular, usually exserted beyond anthers. |
Capsules | somewhat curved and often somewhat twisted, lanceoloid-cylindrical, nearly cylindrical, (20–)30–47 × 7–8 mm, gradually tapering to apex, 6–8 mm, dehiscent nearly throughout their length, valve margins with a conspicuous, irregular, wavy ridge; pedicel 1–5 mm. |
6–25 × 1–3 mm, hard, promptly dehiscent throughout their length. |
Seeds | numerous, in 2 distinct rows per locule, narrowly obovoid, 2.5–3 × 1.2–1.4 mm, embryo 7/8 of seed volume, surface finely reticulate; seed collar with a broad membrane sealing cavity, margin entire. |
obovoid, 1.5–2.5 mm. |
2n | = 14. |
= 14. |
Oenothera psammophila |
Oenothera lavandulifolia |
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Phenology | Flowering May–Jul. | Flowering Apr–Aug. |
Habitat | On barren areas of drifting sand at interface between outcrops of lava and sand dunes. | Local and sparse, on sandy and rocky, calcareous soil, high plains, mountains, often with Artemisia tridentata, Cercocarpus, Juniperus, Pinus edulis, or P. monophylla, sometimes in lower zones with Larrea, or in higher zones with P. ponderosa. |
Elevation | 1500–1700 m. (4900–5600 ft.) | 600–2800 m. (2000–9200 ft.) |
Distribution |
ID |
AZ; CO; KS; NE; NM; OK; SD; TX; WY; Mexico (Nuevo León) |
Discussion | Oenothera psammophila is known only from the dune area north and west of St. Anthony, Fremont County. It is unique in Oenothera because of the exudate produced on the leaves to which sand particles adhere, forming a sand sheath, presumably for protection from the constantly blowing sand particles. It is self-incompatible (W. L. Wagner et al. 1985; Wagner 2005). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Oenothera lavandulifolia is known from southern Fall River County, South Dakota, southeastern Wyoming, and far western Nebraska, through western Kansas, Colorado, eastern and southern Utah, northwestern Oklahoma, and the Texas Panhandle to trans-Pecos Texas, central New Mexico, northern and central Arizona, and eastern Nevada. It also occurs in Nuevo León, Mexico, and may be more widespread in northern Mexico. H. F. Towner (1977) found that O. lavandulifolia is self-incompatible and vespertine. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 10. | FNA vol. 10. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Pachylophus psammophilusa., O. cespitosa var. psammophila | Calylophus hartwegii subsp. lavandulifolius, C. hartwegii var. lavandulifolius, C. lavandulifolius, Galpinsia lavandulifolia, G. lavandulifolia var. glandulosa, O. hartwegii var. lavandulifolia, O. lavandulifolia var. glandulosa |
Name authority | (A. Nelson & J. F. Macbride) W. L. Wagner, Stockhouse & W. M. Klein: Monogr. Syst. Bot. Missouri Bot. Gard. 12: 84. (1985) | Torrey & A. Gray: Fl. N. Amer. 1: 501. (1840) — (as lavandulaefolia) |
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