Boechera repanda |
Boechera lincolnensis |
|
---|---|---|
Greene's rockcress, Yosemite rockcress |
Lincoln rockcress |
|
Habit | Perennials; short- to long-lived; sexual; caudex usually not woody. | Perennials; long-lived; sexual; caudex woody. |
Stems | usually 1 per caudex branch, arising from center of rosette near ground surface, (1–)2–9 dm, densely pubescent proximally, trichomes short- to long-stalked, 2–6-rayed, 0.2–0.5 mm, rarely mixed with simple ones, to 1.5 mm, glabrous or sparsely pubescent distally. |
usually 1 per caudex branch, arising from center of leaf tuft, elevated above ground surface on woody base, 2–4.2 dm, densely pubescent proximally, trichomes short-stalked, 3–6-rayed, 0.1–0.5 mm, similarly pubescent distally. |
Basal leaves | blade broadly oblanceolate to obovate, 7–25(–50) mm wide, margins usually repand to coarsely dentate, rarely entire, not ciliate, surfaces moderately to densely pubescent, trichomes short- to long-stalked, 3–6-rayed, 0.2–0.5 mm. |
blade linear or linear-oblanceolate, 1–2 mm wide, margins entire, rarely ciliate near petiole base, trichomes (simple), to 1 mm, surfaces densely pubescent, trichomes short-stalked, 3–8-rayed, 0.1–0.4 mm. |
Cauline leaves | (3–)8–30, not concealing stem; blade auricles absent, surfaces of distalmost leaves sparsely pubescent. |
10–25, concealing stem proximally; blade auricles absent or, rarely, to 1 mm, surfaces of distalmost leaves densely pubescent. |
Racemes | 7–25-flowered, sometimes branched. |
7–15-flowered, usually unbranched. |
Flowers | erect to ascending at anthesis; sepals glabrous or sparsely pubescent; petals white, 3.5–6 × 0.8–1 mm, glabrous; pollen ellipsoid. |
divaricate-ascending at anthesis; sepals pubescent; petals lavender to purple, 10–12 × 2–3 mm, glabrous or sparsely pubescent (occasionally some trichomes abaxially); pollen ellipsoid. |
Fruiting pedicels | erect to divaricate-ascending, straight, 3–10 mm, glabrous or pubescent, trichomes spreading, usually 2–5-rayed, rarely simple. |
divaricate-ascending, straight to slightly curved proximally, recurved distally, 10–20(–25) mm, pubescent, trichomes appressed, branched. |
Fruits | divaricate-ascending, not appressed to rachis, not secund, usually curved, rarely straight, edges parallel, (3.5–)5–13.5 cm × 2.5–4 mm; valves glabrous or pubescent throughout; ovules 34–50 per ovary; style 0.5–1.5 mm. |
usually widely pendent to ascending, rarely horizontal, not appressed to rachis, not secund, straight, edges parallel, (3.2–)4–5.5 cm × 2–2.5 mm; valves pubescent throughout; ovules 86–120 per ovary; style 0.1–0.3 mm. |
Seeds | uniseriate, 2.5–5(–6) × 2–3(–3.5) mm; wing continuous, 0.7–1.8 mm wide. |
biseriate, 1–1.5 × 0.7–0.9 mm; wing continuous, 0.07–0.12 mm wide. |
2n | = 14. |
= 14. |
Boechera repanda |
Boechera lincolnensis |
|
Phenology | Flowering Jun–Jul. | Flowering Apr–May. |
Habitat | Rock outcrops, talus, and gravelly soil in meadows and open pine forests | Rocky slopes and gravelly soil with sagebrush and other shrubs |
Elevation | 1600-3500 m (5200-11500 ft) | 1400-1900 m (4600-6200 ft) |
Distribution |
CA; NV
|
CA; NV; UT |
Discussion | Boechera repanda is a sexual diploid that is distinguished from all other western North American species by its wide (10–50 mm), repand to coarsely dentate basal leaves. The form recognized as var. greenei appears to be a growth response to ecologically marginal habitats. Boechera repanda occurs sporadically in the Sierra Nevada and Transverse Ranges of California, and barely extends into the Carson Range in western Nevada. Arabis inamoena Greene (1911), not Greene (1908) is an illegitimate name, sometimes found in synonymy with Boechera repanda. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Recent studies suggest that Boechera lincolnensis is a distinct species (see M. D. Windham and I. A. Al-Shehbaz 2006 for detailed comparison). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 402. | FNA vol. 7, p. 388. |
Parent taxa | Brassicaceae > tribe Boechereae > Boechera | Brassicaceae > tribe Boechereae > Boechera |
Sibling taxa | ||
Synonyms | Arabis repanda, Arabis repanda var. greenei | Arabis pulchra var. munciensis, B. pulchra var. munciensis |
Name authority | (S. Watson) Al-Shehbaz: Novon 13: 388. (2003) | Windham & Al-Shehbaz: Harvard Pap. Bot. 11: 71. (2006) |
Web links |
|
|