Draba alpina |
Draba cyclomorpha |
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alpine Draba |
granite Draba, Lemmon's Draba |
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Habit | Perennials; (cespitose); caudex branched (covered with persistent leaves or leaf remains); scapose. | Perennials; (cespitose, not pulvinate); caudex branched (with persistent petiole remains, branches sometimes terminating in sterile rosettes); scapose. |
Stems | unbranched, (0.3–)0.5–1.7(–2.8) dm, pubescent throughout, trichomes simple and 2-rayed, 0.3–0.8 mm, with 3–5-rayed ones, 0.1–0.3 mm. |
unbranched, 0.1–0.6(–1) dm, (thinly) pilose throughout, trichomes simple and stalked, 2- (or 3-)rayed, (often crisped), 0.1–0.8 mm. |
Basal leaves | rosulate; petiolate; petiole base (not thickened), ciliate, (trichomes simple, 0.3–1 mm); blade oblanceolate to obovate or lanceolate to oblong, 0.8–3(–4.5) cm × 2.5–6(–9) mm, margins entire, surfaces abaxially pubescent with stalked, 2–4-rayed trichomes, 0.1–0.5 mm, with simple ones (midvein obscure, not thickened), adaxially glabrous or sparsely pubescent with simple and stalked, 2–4-rayed trichomes. |
rosulate; shortly petiolate; petiole base and margin ciliate, (trichomes simple, 0.2–1 mm); blade (somewhat fleshy), oblanceolate to obovate, 0.4–1 cm × 2–5 mm, margins entire, surfaces glabrous or hirsute, abaxially usually with stalked, 2-rayed trichomes, 0.1–0.6 mm, rarely with fewer, simple ones, (midvein obscure), adaxially with almost exclusively simple trichomes, to 0.6 mm. |
Cauline leaves | 0. |
0. |
Racemes | 6–18-flowered, ebracteate, considerably elongated in fruit; rachis not flexuous, pubescent as stem. |
5–14(–20)-flowered, ebracteate, elongated in fruit; rachis not flexuous, pubescent as stem. |
Flowers | sepals (purplish tinged), narrowly ovate, 2.5–3 mm, pubescent, (trichomes simple and fewer, stalked, 2-rayed); petals bright yellow, narrowly obovate, 3.5–5 × 1.7–2.5 mm; anthers ovate, 0.3–0.4 mm. |
sepals ovate, 1.5–2.2 mm, pubescent, (trichomes simple and short-stalked, 2-rayed); petals yellow, spatulate, 4–5.5 × 1.5–2.5 mm; anthers oblong, 0.6–0.7 mm. |
Fruiting pedicels | ascending to divaricate-ascending, straight or, sometimes, slightly curved upwards, 4–14(–30) mm, pubescent, trichomes simple and 2–4-rayed. |
horizontal to divaricate-ascending, often curved upward or straight, 3–8(–10) mm, pilose as stem. |
Fruits | elliptic, plane, flattened, 6–10 × 2–3 mm; valves glabrous or glabrescent, trichomes simple, (not confined to replum); ovules 12–24 per ovary; style 0.2–0.3 mm (stigma about as wide as style). |
oblong to oblong-ovate, plane, flattened, 3.5–9 × 2.5–4 mm; valves glabrous; ovules 8–12 per ovary; style 0.3–1 mm. |
Seeds | (pale brown), ovoid, 0.9–1.3 × 0.6–0.9 mm. |
ovoid, 1.4–1.9 × 1–1.2 mm. |
2n | = 80. |
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Draba alpina |
Draba cyclomorpha |
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Phenology | Flowering Jun–Aug. | Flowering Jul–Aug. |
Habitat | Moist tundra and ridges, sand and gravel flats or beaches | Basaltic talus, stony ridges |
Elevation | 0-1000 m (0-3300 ft) | 2500-3100 m (8200-10200 ft) |
Distribution |
LB; MB; NU; ON; QC; Greenland; Europe (Finland, Norway, Russia, Sweden)
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OR |
Discussion | The synonymy above includes two North American names overlooked by C. L. Hitchcock (1941) and R. C. Rollins (1993). Draba alpina was broadly delimited by O. E. Schulz (1927) and included 17 varieties, some of which (e.g., corymbosa, oxycarpa, pilosa) are recognized herein as distinct species. The name D. alpina was so misapplied that it was used for any circumpolar or alpine, scapose, yellow-flowered, perennial Draba. Various chromosome numbers (e.g., 2n = 64, 80, 112, 120; S. I. Warwick and I. A. Al-Shehbaz 2006) have been reported for the species. As circumscribed here, it has the narrow distribution outlined above and includes plants with 2n = 80. Reports of the species from Alaska, Canadian Northwest Territories and Yukon, Siberia, eastern Asia, Russian Far East, and the Central Asian republics are either suspect or very unlikely. The entire D. alpina complex (including the above three species, D. glacialis Adams, D. macounii, etc.) is in need of critical molecular, cytological, and morphological study. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Draba cyclomorpha was treated by Schulz, C. L. Hitchcock (1941), and R. C. Rollins (1993) as a variety of D. lemmonii. The two taxa are quite distinct morphologically and separated by nearly 1600 kilometers, justifying their treatment as distinct species (I. A. Al-Shehbaz and M. D. Windham 2007). Draba cyclomorpha is known to us only from the Wallowa Mountains. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 290. | FNA vol. 7, p. 305. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | D. alpina var. hydeana, D. alpina var. inflatisiliqua | D. lemmonii var. cyclomorpha |
Name authority | Linnaeus: Sp. Pl. 2: 642. (1753) | Payson: Amer. J. Bot. 4: 263. (1917) |
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