Draba asprella

Greene

Bull. Torrey Bot. Club 10: 125. 1883.

IllustratedEndemic
Treatment appears in FNA Volume 7. Treatment on page 293. Mentioned on page 284, 347.

Perennials; (cespitose); caudex branched (with some persistent leaf-bases); scapose. Stems unbranched, (0.4–) 0.6–1.5 (–2.7) dm, pubescent throughout, trichomes simple, 0.5–1.5 mm, and 2–4-rayed ones, 0.05–0.3 mm, (sometimes 2–4-rayed ones distally). Basal leaves rosulate; subsessile or shortly petiolate; petiole ciliate throughout; blade oblanceolate to spatulate or obovate, (0.6–) 0.8–4.5 (–6) cm × 2–12 (–16) mm, margins usually entire, rarely obscurely dentate, (not ciliate), surfaces abaxially pubescent with stalked, (2–) 4-rayed trichomes, 0.2–1 mm, adaxially with stalked, 2–4-rayed trichomes, 0.3–0.8 mm, and simple ones, 0.5–1.9 mm. Cauline leaves 0. Racemes (15–) 30–75-flowered, ebracteate, elongated in fruit; rachis not flexuous, pubescent, trichomes 2–4-rayed, sometimes with simple ones. Fruiting pedicels horizontal to divaricate-ascending, straight, 3–11 (–16) mm, pubescent, trichomes 2–4-rayed, sometimes with simple ones. Flowers: sepals broadly ovate, 1.8–3.5 mm, pubescent, (trichomes simple and short-stalked, 2–4-rayed); petals pale-yellow, oblanceolate, 4–7 × 1.5–2.5 mm; anthers ovate to oblong, 0.4–0.7 mm. Fruits ovoid-ellipsoid to oblong, plane, inflated basally, 3–8 × 1.8–3.5 mm; valves hirsute, trichomes simple and spurred, (0.2–) 0.3–1 mm, or puberulent, trichomes short-stalked, 2–4-rayed, 0.1–0.2 mm; ovules 8–12 (–18) per ovary; style 0.6–2 (–2.5) mm. Seeds oblong, 0.9–1.2 × 0.6–0.8 mm. 2n = 30.

Discussion

Varieties 2 (2 in the flora).

Both R. C. Rollins (1993) and N. H. Holmgren (2005b) indicated that the chromosome number of Draba asprella is 2n = 32, but repeated counts by one of us (M. D. Windham 2000, unpubl.) show that the species consistently has 2n = 30. Rollins divided D. asprella into four varieties encompassing tremendous variation in trichome morphology. One of these (var. zionensis) is more closely related to D. sobolifera (Windham and L. Allphin, unpubl.) and is treated herein at species rank. Within D. asprella, in the strict sense, we recognize two varieties separated primarily by the type of trichomes found on the fruits. The distinctions are not absolute and there appear to be forms connecting the two, especially in Coconino County.

Selected References

None.

Key

1 Fruits hirsute, trichomes simple and unequally 2-rayed, (0.2-)0.3-1 mm. Draba asprella var. asprella
1 Fruits puberulent, trichomes 2-4-rayed, 0.1-0.2 mm. Draba asprella var. stelligera

"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 asprella"
ovate +  and oblong +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.07 cm0.7 mm <br />7.0e-4 m <br />) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
Greene +
petiolate +  and subsessile +
appendaged +  and unappendaged +
4.5 cm45 mm <br />0.045 m <br /> (6 cm60 mm <br />0.06 m <br />) +
1.2 cm12 mm <br />0.012 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
not +  and auriculate +
0.8 cm8 mm <br />0.008 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
lobed +, toothed +  and entire +
oblanceolate;spatulate or obovate +
much smaller +  and reduced +
0.2 cm2 mm <br />0.002 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
urceolate +, campanulate +  and tubular +
scapose +  and branched +
sessile +  and petiolate +
well-developed +
distinct +
well-differentiated +
emarginate +  and entire +
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 +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
inflated +, plane +, ovoid-ellipsoid +  and oblong +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
dentate +  and entire +
pinnatifid +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
pale-yellow +
rudimentary +
oblanceolate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
trinucleate +  and 3(-11)-colpate +
Bull. Torrey Bot. Club +
ebracteate;(15-)30-75-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 /> (0.12 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 +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.35 cm3.5 mm <br />0.0035 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 +
procumbent +  and decumbent +
prostrate +  and decumbent +
usually erect +  and ascending +
subsessile +, sessile +  and petiolate +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
persistent +
distinct +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.19 cm1.9 mm <br />0.0019 m <br />) +
Abdra +, Erophila +, Nesodraba +  and Tomostima +
Draba asprella +
species +
short-stalked +, simple +  and stalked +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
cruciform +  and forked +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.02 cm0.2 mm <br />2.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
scapose +  and not +
1.1 cm11 mm <br />0.011 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
horizontal +  and divaricate-ascending +
0.3 cm3 mm <br />0.003 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +