Draba pauciflora |
Draba aleutica |
|
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fewflower Draba |
Aleutian Draba |
|
Habit | Perennials; caudex branched (with persistent, thickened leaf midveins); scapose. | Perennials; (densely matted); caudex branched (with persistent leaf remains, some branches terminating in sterile rosettes); scapose. |
Stems | unbranched, (0.05–)0.1–0.8 dm, pubescent throughout, sometimes sparsely so distally, trichomes simple, 0.3–0.7 mm, and 2–4-rayed, 0.05–0.2 mm. |
unbranched, 0.04–0.4 dm, usually pubescent throughout, sometimes glabrous basally, trichomes simple, 0.1–1 mm, with 2-rayed ones. |
Basal leaves | (not imbricate); rosulate; petiolate; petiole ciliate, (trichomes simple and 2-rayed, 0.4–1.3 mm); blade oblanceolate, 0.5–1.1 cm × 1.5–4 mm, margins entire, (pubescent as petiole, apex acute to subacute, trichomes simple and/or branched), surfaces pubescent, abaxially with simple trichomes, to 1 mm, and stalked, 2–4-rayed ones, 0.1–0.5 mm, adaxially with simple trichomes, 0.4–1 mm, (sometimes glabrous). |
(densely imbricate); rosulate; petiolate; petiole base and margin ciliate, (trichomes simple, to 1.4 mm); blade oblanceolate to spatulate or obovate, 0.4–0.8(–1) cm × 2–3.5(–4.5) mm, margins entire, surfaces usually sparsely to densely pilose with simple trichomes, to 1.4 mm, with much fewer, stalked, 2-rayed ones, (sometimes surfaces glabrous, or adaxially only, midvein obscure abaxially). |
Cauline leaves | 0. |
0. |
Racemes | 2–8-flowered (congested), ebracteate, slightly elongated in fruit; rachis not flexuous, pubescent as stem. |
(1 or) 2–5(–9)-flowered, ebracteate, not or slightly elongated in fruit; rachis not flexuous, pubescent as stem. |
Flowers | sepals ovate, 1.8–2.3 mm, pubescent, (trichomes simple with fewer, short-stalked ones); petals pale yellow, narrowly spatulate to oblanceolate, 2.5–3 × 0.8–1.5 mm; anthers ovate, 0.2–0.3 mm. |
sepals oblong, 2–3 mm, glabrous or sparsely pubescent, (trichomes simple); petals yellowish green to pale yellow, linear-oblanceolate, 3–4 × 0.5–0.8 mm; anthers oblong, 0.4–0.5 mm. |
Fruiting pedicels | divaricate to ascending, straight or slightly curved upward, 1.5–4 mm, pubescent as stem or trichomes branched. |
divaricate, straight, 1.5–4(–6) mm, pubescent, trichomes simple with fewer, 2-rayed, stalked ones. |
Fruits | often obovate, plane, slightly flattened, 5–10 × (3–)3.5–5 mm; valves glabrate or sparsely pubescent, 0.05–0.2 mm; ovules 8–16(–20) per ovary; style 0.05–0.15 mm. |
broadly obovoid to subglobose, plane, slightly flattened, 3–5 × 3–4.5 mm; valves glabrous or pubescent, trichomes simple, 0.1–0.3 mm; ovules 4–8 per ovary; style 0.1–0.4 mm. |
Seeds | ovoid, 1.1–1.6 × 0.7–1 mm. |
oblong, (slightly flattened), 1.4–1.8 × 0.9–1.1 mm. |
2n | = 32. |
|
Draba pauciflora |
Draba aleutica |
|
Phenology | Flowering Jun–Aug. | Flowering May–Jul. |
Habitat | Damp rocky slopes, tundra, swales, dry silt plains | Gravelly soil, retreating snow banks, fellfields |
Elevation | 0-1000 m (0-3300 ft) | 200-400 m (700-1300 ft) |
Distribution |
AK; NT; NU; Greenland; Europe (Norway [Svalbard], Russia); e Asia (Russian Far East, n Siberia) |
AK; e Asia (Russian Far East) |
Discussion | O. E. Schulz (1927) recognized five varieties within Draba pauciflora, of which four were listed from North America. Schulz’s concept of D. pauciflora encompassed multiple taxa that we recognize as separate species, including D. micropetala and D. subcapitata. C. L. Hitchcock (1941) and R. C. Rollins (1993) did not mention D. pauciflora; the latter (and G. A. Mulligan 1974b) referred the North American material to D. adamsii. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Draba aleutica is known in the flora area from the Aleutian Islands (e.g., Atka, Attu) and on the Pribilov Islands (St. Paul), as well as in the Alaskan Peninsula near Ugashik. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 326. | FNA vol. 7, p. 289. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. adamsii | D. behringii |
Name authority | R. Brown: Chlor. Melvill., 266. (1823) | Ekman: Svensk Bot. Tidskr. 30: 522, figs. 3c,d. (1936) |
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