Draba subumbellata

Rollins & R. A. Price

Aliso 12: 25, figs. 1k–n, 4. 1988.

IllustratedEndemic
Treatment appears in FNA Volume 7. Treatment on page 343. Mentioned on page 283, 344.

Perennials; (cespitose, densely pulvinate); caudex branched (densely covered with persistent leaves and remains, branches tightly grouped, sometimes terminating in sterile rosettes); scapose. Stems unbranched, (0.05–) 0.1–0.25 dm, densely pubescent throughout, trichomes (grayish), stalked, dendritic, 5–12-rayed, 0.1–0.25 mm. Basal leaves (densely imbricate); rosulate; sessile; blade obovate to broadly oblong, 0.2–0.4 cm × 0.6–1.5 mm, margins entire, (not ciliate), surfaces densely pubescent, trichomes (grayish), stalked, dendritic, 5–12-rayed, 0.1–0.3 mm, (sometimes with long-stalked and spurred trichomes adaxially). Cauline leaves 0. Racemes 2–5 (–10) -flowered, ebracteate, subumbellate or slightly elongated in fruit; rachis not flexuous, pubescent as stem. Fruiting pedicels divaricate-ascending, straight, 1.5–3 (–6) mm, glabrous or pubescent as stem. Flowers: sepals broadly oblong, 1.8–2.8 mm, pubescent, (trichomes dendritic); petals yellow, spatulate, 2.8–4 × 1–1.5 mm; anthers ovate, 0.3–0.4 mm. Fruits ovoid to ovoid-lanceolate, plane, inflated and sometimes subgibbous basally, flattened distally, 2–5 × 2–3 mm; valves pubescent, trichomes short-stalked, dendritic, 4–12-rayed, (sometimes spurred), 0.05–0.2 mm; ovules 6–12 per ovary; style 0.2–0.6 mm. Seeds oblong, 1–1.2 × 0.5–0.7 mm.


Phenology: Flowering Jul–Aug.
Habitat: Wind-eroded areas, alpine fellfields, rock crevices
Elevation: 3300-4100 m

Discussion

Draba subumbellata is similar to, and sympatric with, D. oligosperma. It is distinguished from the latter by having stalked, stellate to dendritic leaf trichomes, subumbellate racemes, fruiting pedicels 1.5–3.0(–6.0) mm, fruits pubescent with mostly 4–12-rayed trichomes, and well-formed anthers and pollen. By contrast, D. oligosperma has sessile or subsessile, pectinately-branched leaf trichomes, elongated racemes, fruiting pedicels (2–)3–10(–13) mm, fruits glabrous or pubescent with simple and 2-rayed trichomes, and abortive anthers and/or pollen. Draba subumbellata is restricted to the White Mountains (Esmeralda County, Nevada, and Mono County, California) and to Coyote Ridge in the Sierra Nevada (Inyo County, California).

Selected References

None.

Lower Taxa

None.

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

... more about "Draba subumbellata"
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
Rollins & R. A. Price +
appendaged +  and unappendaged +
not +  and auriculate +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
lobed +, toothed +  and entire +
obovate;broadly oblong +
much smaller +  and reduced +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
urceolate +, campanulate +  and tubular +
scapose +  and branched +
sessile +  and petiolate +
well-developed +
distinct +
well-differentiated +
emarginate +  and entire +
Calif. +  and Nev. +
3300-4100 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 />) +
flattened +, subgibbous +, inflated +, plane +, ovoid +  and ovoid-lanceolate +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
Wind-eroded areas, alpine fellfields, rock crevices +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
2.8mm;4mm +
rudimentary +
spatulate +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Flowering Jul–Aug. +
trinucleate +  and 3(-11)-colpate +
subumbellate;ebracteate;2-5(-10)-flowered +
ascending +  and erect +
slender +
not flexuous +
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 />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.28 cm2.8 mm <br />0.0028 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 +  and Endemic +
tetradynamous +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
straight +
procumbent +  and decumbent +
prostrate +  and decumbent +
divaricate-ascending +
pubescent +  and glabrous +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
Abdra +, Erophila +, Nesodraba +  and Tomostima +
Draba subumbellata +
species +
dendritic +, short-stalked +  and stalked +
cruciform +  and forked +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
scapose +  and not +
pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +