Draba jaegeri

Munz & I. M. Johnston

Bull. Torrey Bot. Club 56: 164. 1929.

EndemicConservation concern
Treatment appears in FNA Volume 7. Treatment on page 314. Mentioned on page 288, 312.

Perennials; (densely cespitose); caudex branched (densely covered with persistent leaves, branches sometimes terminating in sterile rosettes); scapose. Stems unbranched, (0.05–) 0.15–0.5 (–0.6) dm, hirsute throughout, trichomes simple, 0.1–0.8 mm, and 2–4-rayed, 0.0.5–0.4 mm. Basal leaves (densely imbricate); rosulate; sessile; blade oblanceolate to ovate, 0.4–1.5 cm × 1.5–3.5 mm, margins entire, (ciliate, trichomes simple, 0.3–1.1 mm), surfaces pubescent abaxially with stalked, (2–) 4–6-rayed trichomes, 0.1–5 mm, (midvein obscure), adaxially glabrous proximally, sparsely pubescent distally with mostly simple trichomes. Cauline leaves 0. Racemes 3–12 (–18) -flowered, ebracteate, slightly elongated in fruit; rachis not flexuous, hirsute as stem. Fruiting pedicels ascending, straight, 2–6 (–8) mm, hirsute as stem. Flowers: sepals oblong, 2.5–3 mm, hirsute, (trichomes simple and stalked, 2–4-rayed); petals white, spatulate, 4.5–6 × 1.5–2 mm; anthers oblong, 0.8–1 mm. Fruits ovate to elliptic, plane, slightly flattened, 4–8 (–11) × 2.5–4.5 mm; valves pubescent, trichomes stalked (2–) 4-rayed, 0.05–0.5 mm; ovules 8–16 per ovary; style (1.2–) 2–4 (–4.5) mm. Seeds oblong, 1.4–2 × 0.9–1 mm. 2n = 54.


Phenology: Flowering Jun–Aug.
Habitat: Limestone outcrops and gravelly soil
Elevation: 2900-3600 m

Discussion

Of conservation concern.

Draba jaegeri is superficially similar to D. hitchcockii, a narrow endemic of the Lost River Range in central Idaho. Both species are cespitose perennials with relatively large, white flowers, and a chromosome number (2n = 54) otherwise unknown in Draba (M. D. Windham 2004). Draba jaegeri is readily distinguished from D. hitchcockii by having fruits pubescent with (2–)4-rayed trichomes, styles (1.2–)2–4(–4.5) mm, fruiting pedicels 2–6(–8) mm, and spatulate petals 1.5–2 mm wide. By contrast, D. hitchcockii has fruits pubescent with mostly simple and 2-rayed trichomes (with 3- or 4-rayed ones), styles (0.8–)1–1.7(–2) mm, fruiting pedicels (2–)4–13(–18) mm, and obovate petals 2–3.5 mm wide. Draba jaegeri is known only from the Charleston Mountains in Clark County.

Selected References

None.

Lower Taxa

None.

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

... more about "Draba jaegeri"
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Ihsan A. Al-Shehbaz +, Michael D. Windham +  and Reidar Elven +
Munz & I. M. Johnston +
appendaged +  and unappendaged +
not +  and auriculate +
0.4 cm4 mm <br />0.004 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
lobed +, toothed +  and entire +
oblanceolate;ovate +
much smaller +  and reduced +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
urceolate +, campanulate +  and tubular +
scapose +  and branched +
sessile +  and petiolate +
well-developed +
distinct +
well-differentiated +
emarginate +  and entire +
2900-3600 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 +
0.8 cm8 mm <br />0.008 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
indehiscent +  and dehiscent +
0.4 cm4 mm <br />0.004 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
flattened +, plane +, ovate +  and elliptic +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Limestone outcrops and gravelly soil +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
4.5mm;6mm +
rudimentary +
spatulate +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Flowering Jun–Aug. +
trinucleate +  and 3(-11)-colpate +
Bull. Torrey Bot. Club +
ebracteate;3-12(-18)-flowered +
ascending +  and erect +
slender +
not flexuous +
mucilaginous +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
0.25 cm2.5 mm <br />0.0025 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 +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
straight +
procumbent +  and decumbent +
prostrate +  and decumbent +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
subsessile +, sessile +  and petiolate +
0.4 cm4 mm <br />0.004 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
persistent +
distinct +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
pubescent +  and glabrous +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Abdra +, Erophila +, Nesodraba +  and Tomostima +
Draba jaegeri +
species +
stalked +  and simple +
cruciform +  and forked +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.05 cm0.5 mm <br />5.0e-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 +