Draba pennellii

Rollins

J. Arnold Arbor. 64: 502. 1983.

EndemicConservation concern
Treatment appears in FNA Volume 7. Treatment on page 329. Mentioned on page 278, 283.

Perennials; (cespitose, often forming mats); caudex branched (elongated, with persistent leaf-bases, branches sometimes terminating in sterile rosettes); sometimes scapose. Stems unbranched, (0.15–) 0.3–0.7 (–1) dm, pubescent proximally, trichomes simple and spurred, 0.4–0.8 mm, and short-stalked, 2–4-rayed, 0.1–0.4 mm, (sometimes with simple trichomes distally). Basal leaves subrosulate; sessile; blade oblanceolate to oblong, (0.3–) 0.5–0.8 cm × 1–3 mm, (base ciliate, trichomes simple, 0.2–0.8 mm), margins entire, (not ciliate), surfaces usually pubescent, with stalked, (2–) 4 (or 5) -rayed trichomes, 0.2–0.5 mm, adaxially sometimes glabrate, or primarily with simple trichomes, 0.3–0.8 mm. Cauline leaves (0 or) 1–4; sessile; blade ovate to oblong, margins entire, surfaces pubescent as basal. Racemes (3–) 7–15 (–20) -flowered, ebracteate, elongated in fruit; rachis not flexuous, pubescent as stem. Fruiting pedicels divaricate-ascending to ascending, straight, 3–10 mm, pubescent, trichomes simple and short-stalked, 2–4-rayed, (0.1–0.4 mm). Flowers: sepals ovate to oblong, 2–3 mm, pubescent, (trichomes simple, with fewer, short-stalked, 2-rayed ones); petals white, obovate, 3.5–6 × 1.5–2.8 mm; anthers oblong, 0.5–0.6 mm. Fruits broadly or, rarely, narrowly lanceolate to elliptic or ovate, plane or slightly twisted, flattened, (4) 5–8 (–10) × 2–3.2 mm; valves (each with distinct midvein), pubescent, trichomes simple and short-stalked, 2-rayed, 0.08–0.2 mm; ovules 12–24 per ovary; style (0.7–) 1–1.8 (–2.1) mm. Seeds oblong, 0.9–1.3 × 0.7–1 mm. 2n = 32.


Phenology: Flowering May–Jul.
Habitat: Rock outcrops and talus slopes in pinyon-juniper, sagebrush, mountain shrub, and mixed conifer communities
Elevation: 1900-3500 m

Discussion

Of conservation concern.

Draba pennellii is known from White Pine County in east-central Nevada. It is easily distinguished from other white-flowered species in the region by its elongated, many-branched caudices, long styles, usually few-leaved or, rarely, leafless flowering stems, and distinct midvein on fruit valves.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."thick" is not a number."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property.

... more about "Draba pennellii"
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
Rollins +
appendaged +  and unappendaged +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
not +  and auriculate +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
lobed +, toothed +  and entire +
ovate;oblong +
much smaller +  and reduced +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
urceolate +, campanulate +  and tubular +
scapose +  and branched +
well-developed +
distinct +
well-differentiated +
emarginate +  and entire +
1900-3500 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
not basally +  and dilated +
actinomorphic +
orange;purple;orange;purple;pink;white;yellow +
spreading +, ascending +  and erect +
linear +, oblanceolate +, spatulate +, obovate +, subsaccate +, not saccate +, oblong +  and ovate +
4 cm40 mm <br />0.04 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
indehiscent +  and dehiscent +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
flattened +, plane +, narrowly lanceolate +  and elliptic or ovate +
0.2 cm2 mm <br />0.002 m <br /> (0.32 cm3.2 mm <br />0.0032 m <br />) +
Rock outcrops and talus slopes in pinyon-juniper, sagebrush, mountain shrub, and mixed conifer communities +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
3.5mm;6mm +
rudimentary +
obovate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.28 cm2.8 mm <br />0.0028 m <br />) +
Flowering May–Jul. +
trinucleate +  and 3(-11)-colpate +
J. Arnold Arbor. +
ebracteate;(3-)7-15(-20)-flowered +
ascending +  and erect +
slender +
not flexuous +
mucilaginous +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
ovate +  and oblong +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
reduced +
latiseptate +, twisted +  and sessile +
indehiscent +  and dehiscent +
terete +, plane +, subglobose +, ovoid +, suborbicular +, linear +, oblong +, elliptic +, lanceolate +  and ovate +
latiseptate +, twisted +  and sessile +
indehiscent +  and dehiscent +
terete +, plane +, subglobose +, ovoid +, suborbicular +, linear +, oblong +, elliptic +, lanceolate +  and ovate +
Endemic +  and Conservation concern +
tetradynamous +
procumbent +  and decumbent +
prostrate +  and decumbent +
usually erect +  and ascending +
subsessile +, sessile +  and petiolate +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
persistent +
distinct +
0.1 cm1 mm <br />0.001 m <br /> (0.18 cm1.8 mm <br />0.0018 m <br />) +
pubescent +  and glabrate +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
Abdra +, Erophila +, Nesodraba +  and Tomostima +
Draba pennellii +
species +
short-stalked +, simple +  and stalked +
cruciform +  and forked +
0.008 cm0.08 mm <br />8.0e-5 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
scapose +  and not +
divaricate-ascending +  and ascending +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +