Draba yukonensis

A. E. Porsild

Publ. Bot. (Ottawa) 4: 37, plate 7. 1975.

IllustratedEndemicConservation concern
Treatment appears in FNA Volume 7. Treatment on page 346. Mentioned on page 274.

Perennials; (short-lived); caudex simple or branched (with persistent leaf remains); not scapose. Stems branched, 0.4–2 dm, pubescent throughout, trichomes simple, 0.3–1.2 mm, and 2–6-rayed, 0.05–0.6 mm. Basal leaves rosulate; subsessile; blade oblanceolate to narrowly so, 0.3–1 cm × 0.5–2 mm, margins entire, (ciliate, trichomes simple, to 1.3 mm), surfaces pubescent, abaxially with (rigid), simple and 2-rayed trichomes, 0.4–1.2 mm, sometimes with short-stalked, 3–6-rayed ones, 0.1–0.3 mm, adaxially with simple trichomes. Cauline leaves 1–3; sessile; blade ovate to oblong, margins entire, surfaces pubescent as basal. Racemes 5–20-flowered, ebracteate, considerably elongated in fruit; rachis not flexuous, pubescent as stem. Fruiting pedicels erect to ascending, straight, 0.5–3 mm, pubescent as stem. Flowers: sepals ovate, 1.2–1.6 mm, pubescent, (trichomes simple and 2–4-rayed); petals white, spatulate, 1.5–2 × 0.7–0.8 mm; anthers ovate, ca. 0.2 mm. Fruits ovoid to oblong, plane, not flattened, 2–5 × 1.5–2 mm; valves pubescent, trichomes short-stalked, 4-rayed or 5-rayed, 0.05–0.3 mm; ovules 36–52 per ovary; style 0.1–0.3 mm. Seeds oblong, 0.6–0.8 × 0.3–0.4 mm.


Phenology: Flowering late May–Jun.
Habitat: Open stony ridges on ancient beach in grassy areas and aspen stands
Elevation: ca. 600 m

Discussion

Of conservation concern.

Draba yukonensis is known only from Kluane National Park, southwestern Yukon Territory.

Selected References

None.

Lower Taxa

None.

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

... more about "Draba yukonensis"
0.2 cm2 mm <br />0.002 m <br /> (?) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
A. E. Porsild +
appendaged +  and unappendaged +
not +  and auriculate +
lobed +, toothed +  and entire +
ovate;oblong +
much smaller +  and reduced +
urceolate +, campanulate +  and tubular +
not scapose +, branched +  and simple +
well-developed +
distinct +
well-differentiated +
emarginate +  and entire +
ca. 600 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 +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
not flattened +, plane +, ovoid +  and oblong +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Open stony ridges on ancient beach in grassy areas and aspen stands +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
pinnatifid +
0.5mm +  and 2mm +
short-stalked +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
1.5mm;2mm +
rudimentary +
spatulate +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
Flowering late May–Jun. +
trinucleate +  and 3(-11)-colpate +
Publ. Bot. (Ottawa) +
ebracteate;5-20-flowered +
ascending +  and erect +
slender +
not flexuous +
mucilaginous +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.16 cm1.6 mm <br />0.0016 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 +
Illustrated +, Endemic +  and Conservation concern +
tetradynamous +
straight +
procumbent +  and decumbent +
prostrate +  and decumbent +
erect +  and ascending +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
Abdra +, Erophila +, Nesodraba +  and Tomostima +
Draba yukonensis +
species +
short-stalked +  and simple +
cruciform +  and forked +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.03 cm0.3 mm <br />3.0e-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 +