Draba incerta |
Draba mogollonica |
|
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whitlow-wort, Yellowstone Draba, Yellowstone Draba whitlow-wort, Yellowstone whitlow-grass, Yellowstone whitlow-wort |
Mogollon Mountain Draba |
|
Habit | Perennials; (cespitose, often pulvinate); caudex branched (dense with persistent leaf remains, branches sometimes terminating in sterile rosettes); scapose. | Annuals, biennials, or, rarely, perennials; (short-lived); not scapose. |
Stems | unbranched, (0.2–)0.4–1.4(–2.1) dm, often pubescent throughout, sometimes glabrous distally, trichomes often simple and 2–5-rayed, 0.1–0.5 mm, (sometimes with mostly subpectinate ones). |
usually branched, (0.6–)1.2–2.8(–3.6) dm, pubescent proximally, glabrous distally, trichomes simple, 0.3–1.3 mm, and 2–4-rayed, 0.1–0.6 mm. |
Basal leaves | rosulate; petiolate; petiole (0–1 cm), ciliate throughout; blade narrowly oblanceolate to linear, (0.4–)0.6–1.7(–2.5) cm × (1–)1.5–3.5(–5) mm, margins entire, (ciliate, trichomes usually simple, rarely 2-rayed, 0.2–1.1 mm), surfaces usually pubescent with short-stalked, pectinate trichomes, 0.15–0.5 mm, sometimes also with 4–6-rayed ones, (midvein usually obscure abaxially), sometimes glabrous adaxially. |
rosulate; petiole (0–2 cm), densely pubescent, (trichomes simple and 2–4-rayed, not ciliate); blade spatulate to obovate or oblanceolate, (1.5–)3–8(–10) cm × 7–25(–33) mm, margins dentate to denticulate, surfaces pubescent with long-stalked, cruciform, and fewer 2- or 3-rayed trichomes, 0.1–0.6 mm. |
Cauline leaves | usually 0 (or 1, as a bract); sessile; blade linear to oblong, margins entire, surfaces pubescent as basal. |
1–3; sessile; blade oblong to ovate, margins entire, surfaces pubescent as basal. |
Racemes | 3–14(–30)-flowered, usually ebracteate, rarely proximalmost flowers bracteate, elongated in fruit; rachis not flexuous, glabrous or pubescent as stem. |
12–40(–51)-flowered, ebracteate, elongated in fruit; rachis not flexuous, usually glabrous, rarely proximally with relatively few trichomes. |
Flowers | sepals broadly ovate, 2.5–3.5(–4) mm, pubescent, (trichomes simple and 2- or 3-rayed); petals yellow (fading white), oblanceolate to obovate, 4–6 × 1.5–2.5 mm; anthers ovate, 0.3–0.5 mm. |
sepals oblong, 2.5–3.5 mm, sparsely pubescent, (trichomes simple and 2–4-rayed); petals yellow, spatulate, (5–)6–8.5 × 2.2–3.5 mm; anthers oblong, 0.7–0.9 mm. |
Fruiting pedicels | ascending, straight, (2.5–)4–11(–27) mm, glabrous or pubescent, trichomes 2–5-rayed or pectinate. |
horizontal to divaricate, straight, (6–)9–18(–22) mm, usually glabrous, rarely sparsely pubescent as stem proximally. |
Fruits | broadly ovate to lanceolate, plane, flattened, 5–9(–11) × 2–4 mm; valves glabrous or puberulent, trichomes simple and 2-rayed, 0.05–0.3 mm; ovules 8–16(–20) per ovary; style 0.2–0.9 mm. |
linear-elliptic to elliptic-lanceolate, slightly twisted, flattened, 6–19 × 2.5–3.5 mm; valves glabrous or pubescent, trichomes simple and short-stalked, 2(–4)-rayed, 0.07–0.3 mm; ovules 24–36 per ovary; style (0.8–)1–2.2 mm. |
Seeds | oblong, 1.1–1.5 × 0.7–1 mm. |
oblong, 1–1.4 × 0.7–0.8 mm. |
2n | = 112. |
= 22. |
Draba incerta |
Draba mogollonica |
|
Phenology | Flowering Jun–Aug. | Flowering Apr–May. |
Habitat | Rock outcrops, talus, gravelly areas, tundra | Rock outcrops and rocky slopes in oak-pine woodlands and mixed conifer communities |
Elevation | 0-3300 m (0-10800 ft) | 1500-2300 m (4900-7500 ft) |
Distribution |
AK; CO; ID; MT; NV; UT; WA; WY; AB; BC; QC; YT
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AZ; NM |
Discussion | Draba incerta was shown by G. A. Mulligan (1972) to be sexually reproducing and 14-ploid with x = 8. It is often confused with the apomict D. oligosperma (2n = 32, 64). Draba incerta is readily separated from D. oligosperma by having well-formed (versus abortive) anthers and pollen, stalked (versus sessile) leaf trichomes, and ciliate (versus non-ciliate) basal leaves with obscure (versus prominent) midveins. Although both species have leafless scapes, one often finds a bract adnate to, or subtending, the proximalmost pedicel in D. incerta. Draba incerta is found near sea level in Alaska. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Draba mogollonica is distributed in New Mexico primarily in the Mogollon and neighboring mountains in Catron, Grant, Sierra, and Socorro counties. It is reported herein for the first time from Arizona from Greenlee County, based on Barneby 2297 (NY), Rollins & Rollins 93113 (CAS, GH), and Windham 2918 (MO, UT). The only published chromosome count (n = 16, compiled in S. I. Warwick and I. A. Al-Shehbaz 2006) is erroneous; counts by M. D. Windham (unpubl.) from five populations representing all of the above-mentioned counties in Arizona and New Mexico consistently agree on n = 11. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 313. | FNA vol. 7, p. 320. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | D. exalata, D. incerta var. laevicapsula, D. incerta var. peasei, D. laevicapsula, D. peasei | |
Name authority | Payson: Amer. J. Bot. 4: 261. (1917) | Greene: Bot. Gaz. 6: 157. (1881) |
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