Draba petrophila |
Draba californica |
|
---|---|---|
Santa Rita Mountain Draba, Santa Rita Mountain whitlowgrass, Santa Rita whitlow grass |
California Draba |
|
Habit | Perennials; (cespitose, long-lived); caudex simple or branched (covered with persistent petioles), not scapose. | Perennials; (short-lived); caudex simple or branched; sometimes scapose. |
Stems | usually unbranched, rarely branched, 0.3–1.9(–2.8) dm, moderately to densely hirsute throughout, trichomes simple, 0.2–1.3 mm, with short-stalked to subsessile, cruciform, 0.02–0.4 mm, and 2-rayed ones, 0.3–0.9 mm. |
unbranched or branched (few), (0.2–)0.4–0.9(–1.2) dm, pubescent throughout, trichomes stellate, 4–8-rayed, 0.05–0.5 mm. |
Basal leaves | rosulate; petiolate; petiole ciliate, (trichomes simple, 0.4–1.5 mm); blade oblanceolate, 1–5(–6) cm × 2–5(–10) mm, margins usually entire, rarely denticulate, surfaces pubescent, abaxially with stalked, cruciform trichomes, 0.07–0.5 mm, adaxially often similar, sometimes with fewer, simple and 2-rayed trichomes, 0.4–1.3 mm. |
rosulate; shortly petiolate; petiole ciliate, margin not ciliate, (trichomes simple and 2-rayed, 0.3–1 mm); blade oblanceolate, 0.6–2 cm × 1.5–4(–6) mm, margins entire, surfaces pubescent with short-stalked, 4–8-rayed trichomes, 0.1–0.4 mm. |
Cauline leaves | 3–10; sessile; blade ovate to lanceolate or oblong, margins entire or denticulate, surfaces pubescent as basal. |
0–3; sessile; blade ovate to oblong, margins entire, surfaces pubescent as basal. |
Racemes | 10–37(–58)-flowered, ebracteate, elongated in fruit; rachis not flexuous, pubescent as stem. |
3–13-flowered, ebracteate, elongated in fruit; rachis not flexuous, pubescent as stem. |
Flowers | sepals oblong, 2–3.5 mm, pubescent, (trichomes simple and 2-rayed); petals yellow, oblanceolate, 3.5–6 × 1.2–1.8 mm; anthers oblong, 0.8–1 mm. |
sepals (persistent until fruit maturity), oblong to ovate, 1.7–2.5 mm, pubescent, (trichomes short-stalked, 2–5-rayed); petals white or creamy white, spatulate to oblanceolate, 2.2–3 × 0.8–1 mm; anthers ovate, 0.2–0.35 mm. |
Fruiting pedicels | divaricate-ascending, straight, 4–10 mm, pubescent throughout, trichomes simple (0.1–0.5 mm) and subsessile, 2–4-rayed, (0.03–0.2 mm). |
ascending to divaricate-ascending, straight, (2–)4–9(–12) mm, pubescent, trichomes short-stalked, 4–8-rayed, (0.1–0.4 mm). |
Fruits | lanceolate to elliptic, often strongly twisted, flattened, 5–11 × 2–3 mm; valves puberulent at least along margin, trichomes simple, antrorse, 0.03–0.15 mm; ovules 14–24 per ovary; style 0.8–1.8(–2.5) mm. |
lanceolate to oblong, plane, slightly flattened, (5–)6–9(–11) × 1.8–2.5 mm; valves usually pubescent, rarely glabrous, trichomes simple and short-stalked, 2- or 3-rayed, 0.05–0.25 mm; ovules 22–32 per ovary; style 0.1–0.3(–0.4) mm. |
Seeds | ovoid, 1–1.4 × 0.6–0.9 mm. |
oblong, 0.8–1 × 0.5–0.6 mm. |
Draba petrophila |
Draba californica |
|
Phenology | Flowering Jul–Sep. | Flowering Jun–Aug. |
Habitat | Crevices, ledges of cliffs | Grassy meadows, alpine areas, fellfields |
Elevation | 1200-2800 m (3900-9200 ft) | 3200-4000 m (10500-13100 ft) |
Distribution |
AZ
|
CA; NV |
Discussion | Draba petrophila is often broadly circumscribed to include the taxon herein called D. viridis. For a discussion of the differences between these species and the closely related D. helleriana, see I. A. Al-Shehbaz and M. D. Windham (2007). Draba petrophila, in the strict sense, is known only from Cochise, Pima, and Santa Cruz counties in southeastern Arizona. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Although originally treated as a variety of Draba cuneifolia, D. californica is but distantly related to that species. Instead, ongoing studies (L. Allphin and M. D. Windham, unpubl.) suggest that it may be an allopolyploid resulting from hybridization between D. albertina and D. breweri. The species is restricted to the White Mountains in Mono County, California, and adjacent Esmeralda County, Nevada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 329. | FNA vol. 7, p. 298. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | D. helleriana var. blumeri, D. helleriana var. petrophila | D. cuneifolia var. californica |
Name authority | Greene: Pittonia 4: 17. (1899) | (Jepson) Rollins & R. A. Price: Aliso 12: 19. (1988) |
Web links |