Draba alpina |
Draba grandis |
|
---|---|---|
alpine Draba |
north Pacific Draba |
|
Habit | Perennials; (cespitose); caudex branched (covered with persistent leaves or leaf remains); scapose. | Perennials; caudex simple or branched (fleshy, with persistent leaf bases); not 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. |
(decumbent), unbranched, (0.2–)0.5–2.7(–3.7) dm, pubescent throughout, trichomes 2–4-rayed, 0.05–0.2 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; long-petiolate; petiole (winged, (1–)4–15 cm), often not ciliate (or ciliate to blade apex, trichomes simple, 0.3–0.8 mm); blade (somewhat fleshy), oblanceolate to spatulate or obovate, (1–)2–11(–17) cm × (5–)8–30(–45) mm, margins often coarsely dentate, (pubescent as petiole), surfaces usually pubescent, abaxially with stalked, 2–4-rayed trichomes, 0.05–0.25 mm, adaxially similar, or also with simple and long-stalked, 2-rayed trichomes, to 0.8 mm, rarely glabrescent, with mostly simple and 2-rayed trichomes. |
Cauline leaves | 0. |
2–12(–16); sessile or petiolate; blade oblanceolate to obovate, margins dentate or entire, surfaces pubescent as basal. |
Racemes | 6–18-flowered, ebracteate, considerably elongated in fruit; rachis not flexuous, pubescent as stem. |
5–26(–32)-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 broadly ovate, 3–4 mm, pubescent, (trichomes simple and short-stalked, 2-rayed); petals yellow, oblanceolate to spatulate, 4.5–7 × 1.8–3 mm; anthers oblong, 0.7–1 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 or ascending, usually straight, rarely curved upward, (5–)10–22(–27) mm, pubescent, trichomes 2–4-rayed (0.05–0.3 mm), sometimes with simple and spurred ones. |
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 lanceolate, or ovate to suborbicular, slightly twisted or plane, flattened, (6–)10–20(–25) × 4–7(–9) mm; valves glabrous; ovules 24–52 per ovary; style (0.2–)0.4–1.6(–2) mm. |
Seeds | (pale brown), ovoid, 0.9–1.3 × 0.6–0.9 mm. |
ovoid, 1.4–2 × 0.8–1.2 mm. |
2n | = 80. |
= 36. |
Draba alpina |
Draba grandis |
|
Phenology | Flowering Jun–Aug. | Flowering May–Jul. |
Habitat | Moist tundra and ridges, sand and gravel flats or beaches | Rocky bluffs above salt-water beaches, loamy seaside banks, sea bird rookeries, coastal herbaceous tundra and sandy blowouts |
Elevation | 0-1000 m (0-3300 ft) | 0-50(-200) m (0-200(-700) ft) |
Distribution |
LB; MB; NU; ON; QC; Greenland; Europe (Finland, Norway, Russia, Sweden)
|
AK; BC; e Asia (Kuril and Ratmanov islands, Russian Far East) |
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.) |
Almost all recent North American authors have used the name Draba hyperborea for this species. A. N. Berkutenko (1995) clearly showed that the type of that name belongs to an entirely different species that she placed in the genus Schivereckia Andrzejowski ex de Candolle. Draba grandis thus becomes the correct name for the North American taxon. Except for its fleshy leaves, Nesodraba is indistinguishable morphologically and molecularly from other species of Draba. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 290. | FNA vol. 7, p. 309. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | D. alpina var. hydeana, D. alpina var. inflatisiliqua | Cochlearia siliquosa, Cochlearia spathulata, D. greenei, D. hatchiae, D. hyperborea var. spathulata, D. spathulata, Nesodraba grandis, Nesodraba megalocarpa, Nesodraba siliquosa |
Name authority | Linnaeus: Sp. Pl. 2: 642. (1753) | Langsdorff ex de Candolle: Syst. Nat. 2: 355. (1821) |
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