Boechera shockleyi |
Boechera parishii |
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Shockley's Rock cress |
dwarf rockcress, Parish's Rock cress |
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Habit | Perennials; usually short-lived; sexual; caudex not woody, (rarely with persistent, crowded leaf bases). | Perennials; short- to long-lived; sexual; caudex often woody. |
Stems | usually 1 per caudex branch, arising from center of rosette near ground surface, (0.8–)2–5 dm, densely pubescent proximally, trichomes short-stalked, 7–12-rayed, 0.1–0.2 mm, densely to sparsely pubescent distally. |
usually 1 per caudex branch, arising from center of rosette near ground surface, 0.3–1.4 dm, densely pubescent proximally, trichomes short-stalked, 2–8-rayed, 0.2–0.4 mm, sparsely pubescent distally. |
Basal leaves | blade oblanceolate, 3–10 mm wide, margins entire, not ciliate, surfaces densely pubescent, trichomes short-stalked, 7–12-rayed, 0.1–0.2 mm. |
blade linear to linear-oblanceolate, 0.5–2 mm wide, margins entire, often ciliate along petiole, trichomes (branched), to 0.6 mm, surfaces densely pubescent, trichomes short-stalked, 6–12-rayed, 0.07–0.15 mm. |
Cauline leaves | 14–60, concealing stem for most of length; blade auricles 0.5–4 mm, surfaces of distalmost leaves densely pubescent. |
2–8, rarely concealing stem proximally; blade auricles absent, surfaces of distalmost leaves densely pubescent. |
Racemes | 20–70-flowered, usually unbranched. |
5–20-flowered, unbranched. |
Flowers | ascending at anthesis; sepals pubescent; petals lavender, 6–9 × 0.8–1.2 mm, glabrous; pollen ellipsoid. |
ascending at anthesis; sepals pubescent; petals lavender to purple, 8–13 × 2.5–4 mm, glabrous; pollen ellipsoid. |
Fruiting pedicels | divaricate-ascending, straight, 7–28 mm, pubescent, trichomes appressed, branched. |
ascending, straight, 3–7 mm, pubescent, trichomes appressed, branched. |
Fruits | divaricate-ascending, not appressed to rachis, not secund, usually curved, rarely straight, edges parallel, 4.5–11 cm × 1.5–2 mm; valves glabrous or sparsely pubescent throughout; ovules 140–190 per ovary; style 0.05–0.6 mm. |
ascending, not appressed to rachis, not secund, straight, edges parallel, 1.5–2.5 cm × 1.8–2.5 mm; valves glabrous; ovules 12–20 per ovary; style 3–8 mm. |
Seeds | sub-biseriate, 1–1.3 × 0.7–0.8 mm; wing distal or, rarely, absent, 0.05–0.1 mm wide. |
uniseriate, 1.5–2 × 1–1.5 mm; wing distal or continuous, 0.05–0.2 mm wide. |
2n | = 14. |
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Boechera shockleyi |
Boechera parishii |
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Phenology | Flowering Apr–May. | Flowering Mar–May. |
Habitat | Rock outcrops (primarily dolomite) and gravelly soil in desert scrub, sagebrush, and pinyon-juniper woodlands | Gravelly hillsides in sagebrush- juniper-pine areas |
Elevation | 1200-2200 m (3900-7200 ft) | 1900-2300 m (6200-7500 ft) |
Distribution |
CA; NV; UT
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CA
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Discussion | Boechera shockleyi is a distinctive sexual species recognizable by the combination of strongly overlapping cauline leaves, a dense covering of minute, 7–12-rayed trichomes, and relatively long, curved, divaricate-ascending fruits with sub-biseriate seeds. It is most similar to B. inyoensis, but differs from that species in its narrower (0.8–1.2 versus 1.2–2 mm) petals, eciliate basal leaves with smaller (0.1–0.2 versus 0.2–0.7 mm) trichomes, greater number (140–190 versus 74–134) of ovules per ovary, and shorter (1–1.3 versus 1.7–2 mm) seeds with distal (versus continuous) wings. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Boechera parishii is a distinctive, long-styled, sexual diploid known only from San Bernardino Mountains in San Bernardino County. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 406. | FNA vol. 7, p. 393. |
Parent taxa | Brassicaceae > tribe Boechereae > Boechera | Brassicaceae > tribe Boechereae > Boechera |
Sibling taxa | ||
Synonyms | Arabis shockleyi | Arabis parishii |
Name authority | (Munz) Dorn: Brittonia 55: 3. (2003) | (S. Watson) Al-Shehbaz: Novon 13: 388. (2003) |
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