Draba grayana |
Draba stenopetala |
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Gray's Draba |
Anadyr Draba, star-flower Draba, star-flower whitlow-grass |
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Habit | Perennials; (densely cespitose); caudex branched (covered with persistent, somewhat thickened, dry petioles); not scapose. | Perennials; (pulvinate); caudex branched (covered with persistent leaves, branches sometimes terminating in sterile rosettes); scapose. |
Stems | unbranched, 0.08–0.6 dm, densely to moderately pubescent throughout, trichomes simple and stalked, 2- or 3-rayed, 0.2–1 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; petiolate; petiole ciliate, (trichomes simple, 0.2–1 mm); blade linear to linear-oblanceolate, (0.4–)0.6–1.5(–2) cm × 1–2 mm, margins entire, (pubescent as petiole), surfaces pubescent abaxially with simple and stalked, 2- or 3-rayed trichomes, 0.1–0.4 mm, adaxially glabrate or subapically sparsely pubescent with simple trichomes. |
(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 | 1–4; sessile; blade linear to linear-oblanceolate, margins entire, surfaces pubescent as basal. |
0. |
Racemes | 5–12(–16)-flowered, usually ebracteate, rarely proximalmost flowers bracteate, slightly elongated in fruit; rachis not flexuous, pubescent as stem. |
2–5-flowered, ebracteate, not or slightly elongated in fruit; rachis slightly flexuous, pubescent as stem. |
Flowers | sepals ovate, 1.5–2 mm, pubescent, (trichomes simple and short-stalked, 2- or 3-rayed); petals bright yellow, spatulate, 3–4.5 × 1–2 mm, (flared, clawed); anthers ovate, 0.3–0.5 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 or slightly curved upward, 1.5–6 mm, pubescent as stem. |
divaricate, straight, 2–5(–7) mm, pubescent as stem. |
Fruits | lanceolate to oblong-lanceolate, slightly twisted or plane, flattened, 4–12 × 1.5–3 mm; valves glabrous or pubescent, trichomes simple, 0.07–0.2 mm; ovules 16–20 per ovary; style 0.4–1.2 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, 1–1.4 × 0.7–1 mm. |
ovoid, 1–1.3 × 0.8–1 mm. |
2n | = 24 ± 3. |
= 24, 64. |
Draba grayana |
Draba stenopetala |
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Phenology | Flowering Jul–Aug. | Flowering May–Jul. |
Habitat | Alpine tundra, fellfields, gravelly wet meadows | Rock outcrops, talus, rocky ridges, alpine tundra |
Elevation | 3500-4000 m (11500-13100 ft) | 100-1900 m (300-6200 ft) |
Distribution |
CO |
AK; YT; e Asia (Russian Far East) |
Discussion | Of conservation concern. Draba grayana is an apomictic species clearly related to D. exunguiculata, with which it is occasionally sympatric (see discussion of 36. D. exunguiculata for distinguishing features). It is known from Chaffe, Clear Creek, Larimer, Park, and Summit counties. (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. 310. | FNA vol. 7, p. 341. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. streptocarpa var. grayana, D. alpicola | D. stenopetala var. purpurea |
Name authority | (Rydberg) C. L. Hitchcock: Revis. Drabas W. N. Amer., 29. (1941) | Trautvetter: Trudy Imp. S.-Petersburgsk. Bot. Sada 6: 11. (1879) |
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