Draba macounii

O. E. Schulz in H. G. A. Engler

in H. G. A. Engler, Pflanzenr. 89[IV,105]: 97. 1927.

Endemic
Treatment appears in FNA Volume 7. Treatment on page 318. Mentioned on page 280, 282, 285, 287, 290.

Perennials; (cespitose); caudex simple or branched (with persistent leaf-bases, branches sometimes terminating in sterile rosettes); scapose. Stems unbranched, (0.06–) 0.1–0.4 (–0.6) dm, usually pubescent, rarely glabrous, trichomes simple and stalked, 2–4-rayed, 0.15–0.9 mm. Basal leaves rosulate; petiole (obscure), margin ciliate, (trichomes simple, 0.3–1 mm); blade oblanceolate to obovate, (0.4–) 0.6–1 (–1.5) cm × (1–) 2–4 mm, margins entire, surfaces usually pubescent abaxially, rarely glabrous, with short-stalked, 2–5-rayed trichomes, 0.1–0.5 mm, adaxially glabrous or pubescent with simple and short-stalked, 2-rayed trichomes. Cauline leaves 0. Racemes 3–10 (–13) -flowered, ebracteate, (subumbellate), slightly elongated in fruit; rachis not flexuous, usually pubescent as stem, rarely glabrous. Fruiting pedicels horizontal to divaricate (not expanded basally), curved upward, 1.5–4.5 (–6) mm, abaxially pubescent as stem, adaxially usually glabrous, rarely throughout. Flowers: sepals ovate, 1.5–2.5 mm, glabrous or pubescent, (trichomes simple and short-stalked, 2-rayed or 3-rayed); petals pale-yellow, spatulate, 2.7–4 × 1–2 mm; anthers ovate, 0.2–0.3 mm. Fruits subglobose to ovoid or ellipsoid, plane, inflated at least basally, 4–8 × 2–4.5 mm; valves glabrous; ovules 10–14 (–16) per ovary; style 0.1–0.5 mm. Seeds ovoid, 1–1.2 × 0.6–0.8 mm. 2n = 64.


Phenology: Flowering Jun–Aug.
Habitat: Rock outcrops, talus, tundra
Elevation: 700-2800 m

Distribution

V7 425-distribution-map.gif

Alta., B.C., Yukon, Alaska, Mont.

Discussion

Draba macounii is often confused with the circumpolar decaploid (2n = 80) D. alpina. Plants of the former have scapes (0.6–)1–4(–6) cm, fruiting pedicels divaricate to horizontal, gently curved, and 1.5–4.5(–6) mm, and petals pale yellow, spatulate, and 2.7–4 × 1–2 mm. By contrast, D. alpina has scapes (3–)5–17(–28) cm, fruiting pedicels divaricate-ascending to ascending, often straight, and (3–)4–14(–30) mm, and petals bright yellow, obovate, and 3.5–5 × 1.7–2.5 mm. R. C. Rollins (1993) indicated that the species occurs in Colorado, but we have not seen any material from that state.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."thick" is not a number.

... more about "Draba macounii"
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
O. E. Schulz in H. G. A. Engler +
sessile +  and petiolate +
appendaged +  and unappendaged +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
not +  and auriculate +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
lobed +, toothed +  and entire +
oblanceolate;obovate +
much smaller +  and reduced +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
urceolate +, campanulate +  and tubular +
scapose +, branched +  and simple +
sessile +  and petiolate +
well-developed +
distinct +
well-differentiated +
emarginate +  and entire +
Alta. +, B.C. +, Yukon +, Alaska +  and Mont. +
700-2800 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 +
latiseptate +, twisted +  and sessile +
indehiscent +  and dehiscent +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
inflated +, plane +, subglobose +  and ovoid or ellipsoid +
0.2 cm2 mm <br />0.002 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Rock outcrops, talus, tundra +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
pale-yellow +
2.7mm;4mm +
rudimentary +
spatulate +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Flowering Jun–Aug. +
trinucleate +  and 3(-11)-colpate +
in H. G. A. Engler, Pflanzenr. +
ebracteate;3-10(-13)-flowered +
ascending +  and erect +
slender +
not flexuous +
glabrous +  and pubescent +
mucilaginous +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.1 cm1 mm <br />0.001 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
pubescent +  and glabrous +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 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 +
tetradynamous +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
procumbent +  and decumbent +
prostrate +  and decumbent +
glabrous +  and pubescent +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
pubescent +  and glabrous +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
Abdra +, Erophila +, Nesodraba +  and Tomostima +
Draba macounii +
species +
short-stalked +, simple +  and stalked +
cruciform +  and forked +
0.015 cm0.15 mm <br />1.5e-4 m <br /> (0.09 cm0.9 mm <br />9.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
scapose +  and not +
pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +