Oenothera triangulata |
Oenothera arida |
|
---|---|---|
prairie beeblossom |
trans-Pecos beeblossom |
|
Habit | Herbs annual, villous proximally, sparsely villous along veins and on margins, usually glabrate, sometimes strigillose distally; from taproot. | Herbs perennial, clumped, strigillose and glandular puberulent throughout, also sparsely villous; from stout roots. |
Stems | ascending, usually well-branched from base and distally, rarely unbranched, 15–60 cm. |
erect, usually branched several cm belowground or from near base, sometimes also branched distally, 20–60(–100) cm. |
Leaves | in a basal rosette and cauline, 1.5–8 × 0.2–0.6(–1.5) cm, blade very narrowly elliptic to oblanceolate or oblong-elliptic, margins entire or weakly sinuate-dentate. |
in a basal rosette and cauline, basal 2–4 × 0.4–0.8 cm, petiole0–0.4 cm, blade narrowly oblanceolate to narrowly spatulate; cauline 0.5–5 × 0.1–0.8 cm, petiole 0–0.3 cm, blade narrowly lanceolate or very narrowly elliptic, margins subentire or sinuate-denticulate. |
Flowers | 3(or 4)-merous, zygomorphic, opening at sunset; floral tube 4–5.5 mm; sepals 4.5–6 mm; petals white, fading pink, elliptic-obovate, 3.5–5 mm; filaments 2–3.5 mm, anthers 1.5–3 mm, pollen 35–65% fertile; style 9–10 mm, stigma surrounded by anthers. |
4-merous, nearly actinomorphic, opening near sunset; floral tube 9–13 mm; sepals 7–9 mm; petals white, fading pink to pale red, slightly unequal, rhombic, 7–8 mm, short-clawed; filaments 3–4 mm, anthers 4–5 mm, pollen 85–100% fertile; style 18–22 mm, stigma exserted beyond anthers at anthesis. |
Capsules | narrowly obovoid, 3(or 4)-winged, furrowed between wings, 7–9 × 3–5 mm, narrowed at base; sessile. |
erect, fusiform, often slightly curved, weakly 4-angled, (9–)13–17 × 2–3 mm, valves with inconspicuous raised midrib; sessile. |
Seeds | (1 or)2–5, yellowishto light brown, 1.5–3.5 × 1–1.5 mm. |
(1–)3 or 4, yellowish or light brown, 2–3.5 × 1–2 mm. |
2n | = 14. |
= 14. |
Oenothera triangulata |
Oenothera arida |
|
Phenology | Flowering Apr–Jul. | Flowering Apr–Aug. |
Habitat | Open, sandy sites. | Sandy flats and washes. |
Elevation | 200–600 m. (700–2000 ft.) | 1300–1800 m. (4300–5900 ft.) |
Distribution |
OK; TX |
TX; Mexico (Chihuahua) |
Discussion | Oenothera triangulata is a PTH species and forms a ring of 14 chromosomes in meiosis. The species is self-compatible and autogamous (P. H. Raven and D. P. Gregory 1972[1973]). It may have been derived from hybridization between O. patriciae and O. suffulta. The species has a relatively narrow distribution across south-central Oklahoma and north-central Texas (Oklahoma in Cleveland, Comanche, Cotton, Grady, Oklahoma, Rogers, Stephens, and Tulsa counties; Texas in Archer, Baylor, Callahan, Clay, Coleman, Crosby, Eastland, Erath, Jones, Montague, Taylor, Throckmorton, Tom Greene, Wichita, Wilbarger, and Young counties). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Oenothera arida is known only from several areas in the foothills of the Davis Mountains in eastern Jeff Davis County, northeastern Presidio County, and northern Brewster County, and from areas near Gallego and Chihuahua in Chihuahua, Mexico. P. H. Raven and D. P. Gregory (1972[1973]) determined O. arida to be self-incompatible. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 10. | FNA vol. 10. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Gaura triangulata, G. hexandra var. triangulata, G. tripetala var. triangulata | Gaura macrocarpa |
Name authority | (Buckley) W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 214. (2007) | W. L. Wagner & Hoch: Syst. Bot. Monogr. 83: 211. (2007) |
Web links |