Draba alpina |
Draba lemmonii |
|
---|---|---|
alpine Draba |
granite Draba, Lemmon's Draba |
|
Habit | Perennials; (cespitose); caudex branched (covered with persistent leaves or leaf remains); scapose. | Perennials; (cespitose, not pulvinate); caudex branched (covered 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, 0.3–1(–1.5) dm, hirsute throughout, trichomes simple, 0.2–0.7 mm, with short-stalked, 2-rayed ones, (smaller). |
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, 0.5–1 mm, midvein obscure); blade (somewhat fleshy), oblanceolate to obovate, 0.4–1(–1.8) cm × 1.5–4(–6) mm, margins entire, surfaces hirsute, abaxially mostly with stalked, 2-rayed trichomes, 0.1–0.8 mm, rarely with fewer, simple ones, adaxially with mostly simple ones, 0.5–1 mm. |
Cauline leaves | 0. |
0. |
Racemes | 6–18-flowered, ebracteate, considerably elongated in fruit; rachis not flexuous, pubescent as stem. |
4–15(–21)-flowered, ebracteate, elongated in fruit; rachis not flexuous, hirsute 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, 2–2.7 mm, pubescent, (trichomes simple, short-stalked, 2-rayed); petals yellow, spatulate, 4–6 × 1.5–2.5 mm; anthers oblong, 0.4–0.6 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 somewhat decurrent basally), straight or curved upward, 4–10(–14) mm, hirsute 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). |
ovate to ovate-lanceolate, slightly twisted, flattened, 4–9 × 3.5–5 mm; valves pubescent, trichomes usually simple, 0.1–0.45 mm, rarely with fewer, short-stalked, 2-rayed ones; ovules 10–14(–16) per ovary; style 0.1–0.6(–0.8) mm. |
Seeds | (pale brown), ovoid, 0.9–1.3 × 0.6–0.9 mm. |
ovoid, 1–1.4 × 0.6–1 mm. |
2n | = 80. |
= 50. |
Draba alpina |
Draba lemmonii |
|
Phenology | Flowering Jun–Aug. | Flowering Jul–Aug. |
Habitat | Moist tundra and ridges, sand and gravel flats or beaches | Granitic rock outcrops, boulder slopes, alpine fellfields |
Elevation | 0-1000 m (0-3300 ft) | 3000-4000 m (9800-13100 ft) |
Distribution |
LB; MB; NU; ON; QC; Greenland; Europe (Finland, Norway, Russia, Sweden)
|
CA
|
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 lemmonii was so broadly circumscribed by C. L. Hitchcock (1941) and R. C. Rollins (1993) that it included plants here assigned to three different species. For a list of features distinguishing D. lemmonii from the recently-segregated D. longisquamosa and D. cyclomorpha, see I. A. Al-Shehbaz and M. D. Windham (2007). Draba lemmonii is apparently restricted to alpine areas of the Sierra Nevada in Fresno, Inyo, Madera, Mono, and Tuolumne counties. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 290. | FNA vol. 7, p. 316. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | D. alpina var. hydeana, D. alpina var. inflatisiliqua | |
Name authority | Linnaeus: Sp. Pl. 2: 642. (1753) | S. Watson: in W. H. Brewer et al., Bot. California 2: 430. (1880) |
Web links |