Draba carnosula |
Draba jaegeri |
|
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Mount Eddy Draba, Mt. Eddy Draba |
Jaeger's Draba |
|
Habit | Perennials; (loosely cespitose); caudex branched (somewhat surculose, with persistent leaf bases, branches sometimes terminating in sterile rosettes); scapose. | Perennials; (densely cespitose); caudex branched (densely covered with persistent leaves, branches sometimes terminating in sterile rosettes); scapose. |
Stems | unbranched, 0.3–1.2 dm, glabrous throughout. |
unbranched, (0.05–)0.15–0.5(–0.6) dm, hirsute throughout, trichomes simple, 0.1–0.8 mm, and 2–4-rayed, 0.0.5–0.4 mm. |
Basal leaves | rosulate; petiolate; petiole (persistent, midvein prominent), ciliate, (trichomes sparse, short-stalked, 2–4-rayed, sometimes with simple ones, 0.2–0.5 mm); blade (somewhat fleshy), oblanceolate or spatulate to obovate, 0.3–1.5 cm × 1.5–5 mm, margins entire, (pubescent as petiole), surfaces glabrous. |
(densely imbricate); rosulate; sessile; blade oblanceolate to ovate, 0.4–1.5 cm × 1.5–3.5 mm, margins entire, (ciliate, trichomes simple, 0.3–1.1 mm), surfaces pubescent abaxially with stalked, (2–)4–6-rayed trichomes, 0.1–5 mm, (midvein obscure), adaxially glabrous proximally, sparsely pubescent distally with mostly simple trichomes. |
Cauline leaves | 0. |
0. |
Racemes | 2–6-flowered, ebracteate, elongated in fruit; rachis not flexuous, glabrous. |
3–12(–18)-flowered, ebracteate, slightly elongated in fruit; rachis not flexuous, hirsute as stem. |
Flowers | sepals ovate, 3–4 mm, glabrous; petals yellow, oblanceolate, 5–7 × 1.3–2 mm; anthers oblong, 0.7–0.9 mm. |
sepals oblong, 2.5–3 mm, hirsute, (trichomes simple and stalked, 2–4-rayed); petals white, spatulate, 4.5–6 × 1.5–2 mm; anthers oblong, 0.8–1 mm. |
Fruiting pedicels | divaricate-ascending, straight, 3–8 mm, usually glabrous, rarely trichomes simple. |
ascending, straight, 2–6(–8) mm, hirsute as stem. |
Fruits | lanceolate to elliptic-lanceolate, plane, strongly flattened, 10–23 × 4–6 mm; valves (each with distinct midvein), glabrous; ovules 8–12 per ovary; style 2–3 mm. |
ovate to elliptic, plane, slightly flattened, 4–8(–11) × 2.5–4.5 mm; valves pubescent, trichomes stalked (2–)4-rayed, 0.05–0.5 mm; ovules 8–16 per ovary; style (1.2–)2–4(–4.5) mm. |
Seeds | (broadly winged), orbicular, 3–4.5 in diam.; (wing 1–1.5 mm wide). |
oblong, 1.4–2 × 0.9–1 mm. |
2n | = 54. |
|
Draba carnosula |
Draba jaegeri |
|
Phenology | Flowering Jun–Jul. | Flowering Jun–Aug. |
Habitat | Open rocky hillsides | Limestone outcrops and gravelly soil |
Elevation | 2800-3100 m (9200-10200 ft) | 2900-3600 m (9500-11800 ft) |
Distribution |
CA |
NV |
Discussion | Of conservation concern. Although Draba carnosula was reduced by Hitchcock to a variety of D. howellii, it differs significantly by having leafless flowering stems, 2–6-flowered racemes, and broadly winged seeds 3–4.5 mm in diam. Draba howellii almost always has 1–3-leaved stems, (5–)7–18(–25)-flowered racemes, and not winged, distally appendaged seeds 1–1.6 mm in diam. Draba carnosula is known only from a few collections from Mount Eddy in Trinity County and the north side of Mount Shasta in Siskiyou County. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Draba jaegeri is superficially similar to D. hitchcockii, a narrow endemic of the Lost River Range in central Idaho. Both species are cespitose perennials with relatively large, white flowers, and a chromosome number (2n = 54) otherwise unknown in Draba (M. D. Windham 2004). Draba jaegeri is readily distinguished from D. hitchcockii by having fruits pubescent with (2–)4-rayed trichomes, styles (1.2–)2–4(–4.5) mm, fruiting pedicels 2–6(–8) mm, and spatulate petals 1.5–2 mm wide. By contrast, D. hitchcockii has fruits pubescent with mostly simple and 2-rayed trichomes (with 3- or 4-rayed ones), styles (0.8–)1–1.7(–2) mm, fruiting pedicels (2–)4–13(–18) mm, and obovate petals 2–3.5 mm wide. Draba jaegeri is known only from the Charleston Mountains in Clark County. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 299. | FNA vol. 7, p. 314. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | D. howellii var. carnosula | |
Name authority | O. E. Schulz: in H. G. A. Engler, Pflanzenr. 89[IV,105]: 82. (1927) | Munz & I. M. Johnston: Bull. Torrey Bot. Club 56: 164. (1929) |
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