Draba monoensis |
Draba stenopetala |
|
---|---|---|
Mono Draba, White Mountains Draba |
Anadyr Draba, star-flower Draba, star-flower whitlow-grass |
|
Habit | Perennials; (usually cespitose); caudex simple or branched (poorly developed, with persistent leaf remains); sometimes scapose. | Perennials; (pulvinate); caudex branched (covered with persistent leaves, branches sometimes terminating in sterile rosettes); scapose. |
Stems | unbranched, (0.05–)0.1–0.4 dm, usually pubescent throughout, rarely sparsely pubescent or glabrous distally, trichomes simple and 2-rayed, (often crisped), 0.1–0.6 mm. |
unbranched, (0.02–)0.07–0.2(–0.3) dm, pubescent throughout, trichomes simple and short-stalked, 2–5-rayed, 0.1–0.5 mm, (sometimes simple ones very sparse). |
Basal leaves | rosulate; subsessile or shortly petiolate; petiole margin ciliate or not; blade narrowly oblanceolate, (0.3–)0.5–1.6(–2) cm × (1–)1.5–3(–4) mm, margins usually entire, rarely subapically denticulate, (ciliate or not), surfaces pubescent with simple and stalked, 2-rayed trichomes, 0.1–0.7 mm, (midvein obscure abaxially). |
(densely imbricate); rosulate; petiolate; petiole base and margin ciliate, (trichomes simple and 2-rayed, 0.2–0.5 mm); blade obovate to oblong-spatulate, 0.2–0.6(–0.8) cm × 1–2(–3) mm, margins entire, surfaces often pubescent with simple and stalked, 2–5-rayed trichomes, 0.2–0.9 mm, sometimes glabrous and trichomes on margins only. |
Cauline leaves | 0–2 (or 3); sessile; blade ovate to oblong, margins entire, surfaces pubescent as basal. |
0. |
Racemes | (3–)6–13(–17)-flowered, ebracteate or proximalmost 1 (or 2) flowers bracteate, not or slightly elongated in fruit; rachis not flexuous, usually pubescent as stem, rarely glabrous. |
2–5-flowered, ebracteate, not or slightly elongated in fruit; rachis slightly flexuous, pubescent as stem. |
Flowers | sepals (persistent), oblong, 1–1.5 mm, subapically sparsely pubescent, (trichomes simple); petals white, spatulate, 1.5–2 × 0.5–0.6 mm; anthers ovate, 0.15–0.2 mm. |
sepals (spreading or reflexed), oblong, 2–3.5 mm, pubescent, (trichomes simple and 2-rayed); petals yellow or purple, linear, 2.5–5 × 0.3–0.7 mm; anthers ovate, 0.3–0.4 mm. |
Fruiting pedicels | divaricate-ascending, straight, 1–2.5(–4) mm, usually pubescent as stem, rarely glabrous. |
divaricate, straight, 2–5(–7) mm, pubescent as stem. |
Fruits | ovoid to subellipsoid, plane, slightly inflated basally, (2–)3–5 × (1.2–)1.5–2.5 mm; valves usually puberulent, rarely glabrous, trichomes simple, 0.05–0.2 mm; ovules 12–20 per ovary; style 0.1–0.2 mm. |
suborbicular, plane, inflated basally, flattened distally, 3–5 × 3–4 mm; valves glabrous or puberulent, trichomes simple, 0.02–0.3 mm; ovules 4–10 per ovary; style 0.2–0.6 mm. |
Seeds | ovoid, 0.6–0.8 × 0.4–0.6 mm. |
ovoid, 1–1.3 × 0.8–1 mm. |
2n | = 24, 64. |
|
Draba monoensis |
Draba stenopetala |
|
Phenology | Flowering Jul–Aug. | Flowering May–Jul. |
Habitat | Gravelly alpine meadows | Rock outcrops, talus, rocky ridges, alpine tundra |
Elevation | 3600-4000 m (11800-13100 ft) | 100-1900 m (300-6200 ft) |
Distribution |
CA |
AK; YT; e Asia (Russian Far East) |
Discussion | Of conservation concern. Draba monoensis appears to be polyploid (M. D. Windham, unpubl.), and its morphological similarity to D. fladnizensis (R. C. Rollins 1993) may indicate that the latter is one of its progenitors. The species is known from the White Mountains of Mono County. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Different chromosome counts for Draba stenopetala were reported as 2n = 24 from North America and 2n = 64 from the Russian Far East (S. I. Warwick and I. A. Al-Shehbaz 2006). It is unlikely that a single species is involved, and further work is needed to verify the counts from North America. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 320. | FNA vol. 7, p. 341. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. stenopetala var. purpurea | |
Name authority | Rollins & R. A. Price: Aliso 12: 22, figs. 1f–j, 3. (1988) | Trautvetter: Trudy Imp. S.-Petersburgsk. Bot. Sada 6: 11. (1879) |
Web links |