Boechera perstellata |
Boechera harrisonii |
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Habit | Perennials; usually short-lived; sexual; caudex not woody. | Perennials; long-lived; (some-what cespitose); apomictic; caudex often woody. |
Stems | usually 2–5 per plant, arising from margin of rosette near ground surface, (1–)2–8 dm, densely pubescent proximally, trichomes short-stalked, 3- or 4-rayed, 0.1–0.5 mm, similarly pubescent distally. |
usually 3–7 per caudex branch, arising from margin of rosette near ground surface, 0.5–2.5 dm, usually sparsely pubescent proximally, rarely glabrous, trichomes short-stalked, 2- or 3-rayed, 0.06–0.2 mm, glabrous distally. |
Basal leaves | blade obovate to oblanceolate, (5–)10–45 mm wide, margins usually coarsely dentate, rarely sinuate, ciliate on petiole base, surfaces moderately pubescent, trichomes short-stalked, 3- or 4(–6)-rayed, 0.1–0.5 mm. |
blade narrowly oblanceolate, 2–4 mm wide, margins entire or somewhat dentate, ciliate near petiole base, trichomes (simple), to 0.5 mm, surfaces sparsely pubescent, trichomes short-stalked, 2–5-rayed, 0.1–0.25 mm. |
Cauline leaves | 6–25, concealing stem proximally; blade auricles 1–6 mm, surfaces of distalmost leaves pubescent. |
3–7, not concealing stem; blade auricles 0.5–1.5 mm, surfaces of distalmost leaves glabrous. |
Racemes | 10–40-flowered, usually unbranched. |
5–12-flowered, usually unbranched. |
Flowers | ascending at anthesis; sepals pubescent; petals purplish, 3–4 × 0.7–1 mm, glabrous; pollen ellipsoid. |
ascending at anthesis; sepals pubescent; petals lavender, 5–7.5 × 0.8–1.5 mm, glabrous; pollen spheroid. |
Fruiting pedicels | usually horizontal, usually straight, rarely slightly curved, 5–15 mm, pubescent, trichomes spreading, simple. |
divaricate-ascending, straight, 8–12 mm, glabrous. |
Fruits | usually horizontal, not appressed to rachis, not secund, straight, edges parallel, (1.5–)2–3.3 cm × 0.8–1 mm; valves sparsely pubescent throughout; ovules 12–20 per ovary; style 0.4–0.8 mm. |
usually divaricate-ascending, rarely nearly horizontal, not appressed to rachis, not secund, curved to straight, edges parallel, 3–4.7 cm × 1–1.5 mm; valves glabrous; ovules 64–86 per ovary; style 0.2–0.5 mm. |
Seeds | uniseriate, 0.8–1.1 × 0.6–0.8 mm, not winged. |
uniseriate, 1.1–1.3 × 0.8–1.1 mm; wing continuous, 0.08–0.1 mm wide. |
2n | = 14. |
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Boechera perstellata |
Boechera harrisonii |
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Phenology | Flowering Apr–May. | Flowering May–Jun. |
Habitat | Calcareous bluffs and wooded hillsides | Limestone and quartzite cliffs |
Elevation | 200-400 m (700-1300 ft) | 1500-1600 m (4900-5200 ft) |
Distribution |
KY; TN |
UT |
Discussion | Of conservation concern. Boechera perstellata is in the Center for Plant Conservation’s National Collection of Endangered Plants. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Morphological evidence suggests that Boechera harrisonii is an apomictic species that arose through hybridization between B. microphylla and B. perennans (see M. D. Windham and I. A. Al-Shehbaz 2007 for detailed comparison). Boechera harrisonii is known only from Utah and Wasatch counties in north-central Utah. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 396. | FNA vol. 7, p. 383. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Arabis perstellata, Arabis perstellata var. ampla | Arabis harrisonii, B. microphylla var. harrisonii |
Name authority | (E. L. Braun) Al-Shehbaz: Novon 13: 388. (2003) | (S. L. Welsh) Windham & Al-Shehbaz: Harvard Pap. Bot. 11: 266. (2007) |
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