Draba paucifructa |
Draba daviesiae |
|
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Charleston Mountain Draba |
bitter root Draba |
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Habit | Perennials; caudex simple or branched (not fleshy, usually with some persistent leaf remains); sometimes scapose. | Perennials; (densely pulvinate); caudex branched (branches elongated, loose, with persistent leaf remains, terminating in flowering or sterile shoots); scapose. |
Stems | unbranched, (0.1–)0.3–0.9 dm, glabrous throughout or sparsely pubescent proximally, trichomes simple and 2–6-rayed, 0.1–0.5 mm. |
unbranched, (0.05–)0.2–0.6 dm, glabrous. |
Basal leaves | rosulate; petiolate; petiole (0–0.5 cm), ciliate throughout; blade oblanceolate to obovate, 0.4–1.7(–2.3) cm × 1.6–4(–6) mm, margins usually entire, rarely denticulate, (sparsely ciliate, trichomes simple, 0.3–0.8 mm), surfaces pubescent, abaxially with stalked, (2–)4(–6)-rayed trichomes, (0.05–)0.1–0.6 mm, adaxially with simple and fewer, stalked, 2–4-rayed ones. |
(densely imbricate); rosulate; petiolate; petiole ciliate throughout; blade (fleshy), oblong to obovate or oblanceolate, 0.3–0.7(–1) cm × 1–2(–2.5) mm, margins entire, (ciliate, trichomes simple, 0.1–0.5 mm, apex obtuse), surfaces glabrous (midvein obscure abaxially). |
Cauline leaves | 0 or 1; sessile; blade ovate to lanceolate, margins entire, surfaces pubescent as basal. |
0. |
Racemes | (2–)4–9(–12)-flowered, ebracteate, elongated in fruit; rachis slightly flexuous, glabrous. |
2–8(–10)-flowered, ebracteate, (subcorymbose), slightly elongated in fruit; rachis not flexuous, glabrous. |
Flowers | sepals ovate, 1.2–1.7 mm, pubescent, (trichomes simple and short-stalked, 2- or 3-rayed); petals yellowish (quickly fading white), spatulate, 1.8–2.2 × 0.6–1 mm; anthers ovate, 0.25–0.3 mm. |
sepals oblong, 1.5–2.2 mm, glabrous; petals pale to bright yellow, spatulate, 3.5–4 × 1–2 mm; anthers ovate, 0.3–0.4 mm. |
Fruiting pedicels | divaricate-ascending, straight, 2–5(–8) mm, glabrous. |
divaricate-ascending (not decurrent basally), straight, 4–10 mm, glabrous. |
Fruits | elliptic to linear lanceolate, plane, flattened, 5–10(–12) × 1.7–2(–2.5) mm; valves glabrous; ovules 20–30 per ovary; style 0.08–0.2 mm. |
ovate to oblong-elliptic, plane, flattened, 4–8 × 2–4 mm; valves (obscurely veined), glabrous; ovules 6–14 per ovary; style 0.1–0.5 mm. |
Seeds | oblong, 0.9–1.2 × 0.5–0.8 mm. |
ovoid, 1.2–1.5 × 0.8–1 mm. |
2n | = 40. |
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Draba paucifructa |
Draba daviesiae |
|
Phenology | Flowering Jun–Jul. | Flowering Jul–Aug. |
Habitat | Moist, shaded slopes among limestone and dolomite rocks | Talus slopes, rock crevices and cracks, rocky ridges and slides, alpine meadows |
Elevation | 2600-3500 m (8500-11500 ft) | 2700-2900 m (8900-9500 ft) |
Distribution |
NV |
MT |
Discussion | Of conservation concern. Draba paucifructa is known from the Charleston Mountains in Clark County. M. D. Windham (2004) suggested that it is an allopolyploid resulting from hybridization between D. albertina and D. lonchocarpa, and he discussed the morphological features that distinguish this species from its putative parents. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Although originally described as a variety of Draba apiculata (= D. globosa), D. daviesiae is distinct morphologically. It is easily distinguished from the former by its densely pulvinate habit, obtuse leaf blades, and obscurely veined fruit valves. By contrast, D. globosa exhibits a cespitose but non-pulvinate habit, acute leaf blades, and prominently veined fruit valves. Draba daviesiae is known from the Bitterroot Mountains in Ravalli County. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 327. | FNA vol. 7, p. 305. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. apiculata var. daviesiae, D. densifolia var. daviesiae | |
Name authority | Clokey & C. L. Hitchcock: Madroño 5: 127. (1939) | (C. L. Hitchcock) Rollins: Contr. Gray Herb. 214: 5. (1984) |
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