Draba alpina |
Draba longisquamosa |
|
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alpine Draba |
granite Draba |
|
Habit | Perennials; (cespitose); caudex branched (covered with persistent leaves or leaf remains); scapose. | Perennials; (cespitose); 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, 0.2–0.9 dm, hirsute throughout, trichomes simple, 0.2–0.8 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, 0.1–1 mm); blade oblanceolate to obovate, 0.5–2 cm × 2–5 mm, margins entire, surfaces pubescent with simple trichomes, 0.15–0.8 mm. |
Cauline leaves | 0. |
0. |
Racemes | 6–18-flowered, ebracteate, considerably elongated in fruit; rachis not flexuous, pubescent as stem. |
4–16-flowered, ebracteate, (subumbellate), slightly 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 (persistent) ovate, 1.5–2.2 mm, pubescent, (trichomes simple); petals (persistent), yellow, spatulate, 3.5–5 × 1.5–2 mm; anthers oblong, 0.5–0.6 mm. |
Fruiting pedicels | ascending to divaricate-ascending, straight or, sometimes, slightly curved upwards, 4–14(–30) mm, pubescent, trichomes simple and 2–4-rayed. |
divaricate to ascending (not decurrent basally), straight, 3–7 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 suborbicular, plane, flattened, 3.5–7 × 2.5–5 mm; valves pubescent, trichomes simple, 0.1–0.3 mm; ovules 10–16 per ovary; style 0.4–1 mm. |
Seeds | (pale brown), ovoid, 0.9–1.3 × 0.6–0.9 mm. |
ovoid, 1–1.2 × 0.7–0.8 mm. |
2n | = 80. |
|
Draba alpina |
Draba longisquamosa |
|
Phenology | Flowering Jun–Aug. | Flowering Jul. |
Habitat | Moist tundra and ridges, sand and gravel flats or beaches | Gravelly areas |
Elevation | 0-1000 m (0-3300 ft) | 3000-3900 m (9800-12800 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 longisquamosa was treated as a synonym of D. lemmonii by both C. L. Hitchcock (1941) and R. C. Rollins (1993). We feel that the two taxa show sufficient morphological divergence and merit recognition as separate species (see I. A. Al-Shehbaz and M. D. Windham 2007 for more detailed discussion). Draba longisquamosa is currently known only from the southern Sierra Nevada in Fresno, Inyo, and Tulare counties. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 290. | FNA vol. 7, p. 317. |
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) | O. E. Schulz: in H. G. A. Engler, Pflanzenr. 89[IV,105]: 94. (1927) |
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