Boechera tularensis |
Boechera pinzliae |
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Tulare rockcress |
Pinzl's Rock cress |
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Habit | Biennials or perennials; short-lived; apomictic; caudex present or absent. | Perennials; long-lived; apomictic; caudex usually woody. |
Stems | usually 1 per caudex branch, arising from center of rosette near ground surface, 2–7 dm, sparsely to densely pubescent proximally, trichomes subsessile, sub-malpighiaceous, 0.3–0.6 mm, glabrous distally. |
1–3 per caudex branch, arising from margin of rosette near ground surface, 0.4–1.6 dm, densely pubescent proximally, trichomes short-stalked, 2–5-rayed, 0.05–0.2 mm, glabrous or sparsely pubescent distally. |
Basal leaves | blade oblanceolate, 3–7 mm wide, margins entire, ciliate proximally, trichomes (simple), to 0.8 mm, surfaces sparsely to densely pubescent, trichomes subsessile, 2–5-rayed, 0.2–0.55 mm. |
(petiole glabrous); blade linear-oblanceolate, 1–3 mm wide, margins entire, rarely ciliate proximally, trichomes to 0.5 mm, surfaces densely pubescent, trichomes short-stalked, 2–5-rayed, 0.05–0.2 mm. |
Cauline leaves | 7–17, often concealing stem proximally; blade auricles 2–5 mm, surfaces of distalmost leaves sparsely pubescent or glabrous. |
3–6, not concealing stem; blade auricles 0(–0.3) mm, surfaces of distalmost leaves sparsely to moderately pubescent. |
Racemes | 19–39-flowered, usually unbranched. |
5–8-flowered, unbranched. |
Flowers | divaricate to pendent at anthesis; sepals pubescent; petals white to pale lavender, 6–7 × 1.2–2 mm, glabrous; pollen spheroid. |
ascending at anthesis; sepals pubescent; petals purple, 4–5 × 1–1.5 mm, glabrous; pollen spheroid. |
Fruiting pedicels | reflexed, recurved proximally, 5–13 mm, glabrous. |
ascending to divaricate-ascending, straight, 2–6 mm, glabrous or sparsely pubescent, trichomes appressed, branched. |
Fruits | reflexed, rarely appressed to rachis, not secund, straight, edges parallel, 4–7(–8.5) cm × 2–2.3 mm; valves glabrous; ovules 88–104 per ovary; style 0.3–0.7 mm. |
ascending to divaricate-ascending, not appressed to rachis, not secund, straight, edges parallel, 2.5–4.8 cm × 2.5–3.2 mm; valves glabrous; ovules 26–34 per ovary; style 0.1–0.3 mm. |
Seeds | sub-biseriate, 2–2.5 × 1.1–1.5 mm; wing continuous, 0.15–0.25 mm wide. |
uniseriate, 2.5–3.5 × 1.5–2.5 mm; wing continuous, 0.2–0.9 mm wide. |
Boechera tularensis |
Boechera pinzliae |
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Phenology | Flowering Jun–Jul. | Flowering Jul. |
Habitat | Rocky slopes in montane and subalpine habitats | Gravelly granitic soils in alpine and subalpine areas |
Elevation | 2400-3200 m (7900-10500 ft) | 3000-3400 m (9800-11200 ft) |
Distribution |
CA |
CA; NV |
Discussion | Morphological evidence suggests that Boechera tularensis is an apomictic species that contains three different genomes, one each from B. rectissima, B. retrofracta, and B. stricta. It is most often confused with B. pinetorum and B. retrofracta, but is easily distinguishable from both (see M. D. Windham and I. A. Al-Shehbaz 2007b for detailed comparison). It is known from the southern Sierra Nevada (Fresno and Tulare counties). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Morphological evidence suggests that Boechera pinzliae is an apomictic hybrid that contains at least one genome derived from B. platysperma; the other parent has not yet been determined. It is most similar to B. elkoensis, from which it differs in having sparsely pubescent (versus glabrous) sepals and basal leaves with stalked (versus sessile or subsessile) trichomes. Boechera pinzliae is known only from the White Mountains in extreme western Nevada (Esmeralda County) and east-central California (Mono County). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 410. | FNA vol. 7, p. 397. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Arabis pinzliae | |
Name authority | Windham & Al-Shehbaz: Harvard Pap. Bot. 12: 249. (2007) | (Rollins) Al-Shehbaz: Novon 13: 388. (2003) |
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