Boechera lemmonii |
Boechera bodiensis |
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Lemmon's rock-cress, Lemmon's suncress, wind-blown suncress |
Bodie Hills rock cress |
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Habit | Perennials; long-lived; (somewhat cespitose); sexual or apomictic; caudex woody. | Perennials; long-lived; (cespitose); apomictic; caudex somewhat woody. |
Stems | usually 1 per caudex branch, arising from center of rosette near ground surface, or arising laterally proximal to sterile shoots, 0.5–2(–2.5) dm, glabrous or sparsely pubescent proximally, trichomes short-stalked, 2–6-rayed, 0.1–0.2 mm, glabrous distally. |
usually 1 per caudex branch, arising from center of rosette near ground surface, 1.5–3.5 dm, densely pubescent proximally, trichomes short-stalked, 5–10-rayed, to 0.7 mm, sparsely pubescent or glabrous distally. |
Basal leaves | blade oblanceolate to obovate, 1.5–5 mm wide, margins usually entire, rarely slightly dentate, ciliate along petiole, surfaces densely to sparsely pubescent, trichomes short-stalked, 3–9-rayed, 0.1–0.2 mm. |
blade narrowly oblanceolate, 1–3 mm wide, margins entire, ciliate proximally, trichomes to 0.7 mm, surfaces densely pubescent, trichomes short-stalked, 5–10-rayed, 0.08–0.25 mm. |
Cauline leaves | 2–8(–12), not concealing stem; blade auricles absent or 0.1–0.5 mm, surfaces of distalmost leaves glabrous or sparsely pubescent. |
4–9, not concealing stem; blade auricles 0.5–2 mm, surfaces of distalmost leaves pubescent. |
Racemes | 3–12(–17)-flowered, usually unbranched. |
8–25-flowered, usually unbranched. |
Flowers | divaricate-ascending at anthesis; sepals glabrous or sparsely pubescent; petals purple to lavender, 3.5–6 × 1–1.5 mm; pollen ellipsoid or spheroid. |
ascending at anthesis; sepals pubescent; petals lavender to purple, 4–5 × ca. 1 mm, glabrous; pollen spheroid. |
Fruiting pedicels | divaricate-ascending to slightly descending, usually slightly recurved, rarely straight, 2–6 mm, glabrous or sparsely pubescent, trichomes appressed, branched. |
ascending to divaricate-ascending, straight, 3–7 mm, pubescent, trichomes appressed, branched. |
Fruits | divaricate-ascending to slightly descending, not appressed to rachis, secund, straight or curved, edges parallel, (1.6–) 2–4.4 cm × 1.6–2.3 mm; valves glabrous; ovules 28 40(–44) per ovary; style 0.1–0.2 mm. |
divaricate-ascending, not appressed to rachis, not secund, straight or curved, edges parallel, 4–6.2 cm × 1.2–1.8 mm; valves glabrous; ovules 48–68 per ovary; style 0.1–0.2 mm. |
Seeds | uniseriate, 1.3–2 × 1–1.5 mm; wing continuous, 0.1–0.5 mm wide. |
uniseriate, 1–1.5 × 0.8–1.2 mm; wing continuous, 0.1–0.15 mm wide. |
2n | = 14. |
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Boechera lemmonii |
Boechera bodiensis |
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Phenology | Flowering Jun–Aug. | Flowering Jul–Aug. |
Habitat | Cliffs, talus slopes, and gravelly soil in alpine and subalpine habitats | Loose soil, crevices of igneous rock |
Elevation | 2100-4400 m (6900-14400 ft) | 2400-2900 m (7900-9500 ft) |
Distribution |
AK; CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC; YT
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CA; NV |
Discussion | Boechera lemmonii is easily recognized by its combination of secund fruits, mat-forming habit, purplish sepals, and obovate-oblanceolate cauline leaves. Both sexual and apomictic collections are known; further study is needed to determine whether they truly are conspecific. The taxa traditionally treated as Arabis (Boechera) lemmonii vars. depauperata, drepanoloba, and paddoensis are apomictic hybrids here recognized as distinct species (see M. D. Windham and I. A. Al-Shehbaz 2007 for detailed comparison). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. In his original description, Rollins suggested that Boechera bodiensis is closely related to B. cobrensis and B. falcifructa. Subsequent studies (M. D. Windham and I. A. Al-Shehbaz, unpubl.) indicate that both B. bodiensis and B. falcifructa are apomictic hybrids containing one or more genomes derived from B. cobrensis. In the case of B. falcifructa, the second parent is clearly B. fernaldiana, but the second parent of B. bodiensis remains uncertain. Boechera bodiensis is most similar to B. falcifructa. The latter differs by having gently recurved fruiting pedicels 6–12 mm, 62–80 ovules per ovary, and pendulous fruits; it is known from Elko and Lander counties, Nevada. By contrast, B. bodiensis has straight fruiting pedicels 3–7 mm long, divaricate-ascending fruits, 48–68 ovules per ovary, and is known from Mono County, California, and Lyon and Mineral counties, Nevada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 388. | FNA vol. 7, p. 367. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Arabis lemmonii, Arabis bracteolata, Arabis canescens var. latifolia, Arabis codyi, Arabis egglestonii, Arabis kennedyi, Arabis latifolia, Arabis oreocallis, Arabis polyclada, Arabis semisepulta | Arabis bodiensis |
Name authority | (S. Watson) W. A. Weber: Phytologia 51: 370. (1982) | (Rollins) Al-Shehbaz: Novon 13: 384. (2003) |
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