Boechera pygmaea

(Rollins) Al-Shehbaz

Novon 13: 388. 2003.

Basionym: Arabis pygmaea Rollins Rhodora 43: 476, fig. 1941
Treatment appears in FNA Volume 7. Treatment on page 401. Mentioned on page 353.

Perennials; usually long-lived; sexual; caudex woody, (often with persistent, crowded leaf-bases). Stems usually 2–5 per caudex branch, arising from margin of rosette near ground surface, or arising laterally proximal to sterile shoots, 0.2–0.8 dm, pubescent proximally, trichomes simple and short-stalked, 2-rayed or 3-rayed, to 0.4 mm, glabrescent distally. Basal leaves: blade linear, 0.8–1.5 mm wide, margins entire, ciliate, trichomes (simple and spurred), to 0.8 mm, surfaces moderately pubescent, trichomes short-stalked, 2–4-rayed, 0.05–0.4 mm. Cauline leaves: 2–4, not concealing stem; blade auricles absent, surfaces of distalmost leaves pubescent. Racemes 2–5-flowered, unbranched. Fruiting pedicels erect to ascending, straight, 2–7 mm, usually pubescent, rarely glabrous, trichomes subappressed, branched. Flowers erect at anthesis; sepals pubescent; petals white, 3.5–5 × 0.7–1 mm, glabrous; pollen ellipsoid. Fruits erect to ascending, often appressed to rachis, not secund, straight, edges parallel, (1.3–) 2–3.3 cm × 4–5 mm; valves glabrous; ovules 8–12 per ovary; style 0.05–0.4 mm. Seeds uniseriate, 3–5 × 2.5–4.5 mm; wing continuous, 0.8–2 mm wide distally.


Phenology: Flowering May–Jul.
Habitat: Barren flats of arkosic gravel
Elevation: 2400-3200 m

Discussion

Of conservation concern.

Despite the distinctive morphology of Boechera pygmaea, there is evidence that it is capable of producing fertile hybrids with B. stricta. It is known only from Inyo and Tulare counties in the southern Sierra Nevada.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."thick" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Boechera pygmaea"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +  and Michael D. Windham +
(Rollins) Al-Shehbaz +
not +  and rosulate +
Arabis pygmaea +
appendaged +  and unappendaged +
not +  and auriculate +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
much smaller +  and reduced +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and sessile +
well-developed +
indistinct +
not +  and differentiated +
emarginate +  and entire +
1.3 cm13 mm <br />0.013 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2 cm20 mm <br />0.02 m <br /> (3.3 cm33 mm <br />0.033 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
2400-3200 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
straight +
erect +  and ascending +
torulose +, falcate +, lanceolate +, oblong +  and linear +
Barren flats of arkosic gravel +
annular +  and semiannular +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
pinnatifid +
prominent +  and obscure +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
3.5mm;5mm +
rudimentary +
oblanceolate +  and spatulate +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Flowering May–Jul. +
trinucleate +  and 3(-11)-colpate +
ellipsoid +
unbranched;2-5-flowered +
reflexed +, ascending +  and erect +
slender +
mucilaginous +
margined +, not winged +  and winged +
biseriate +, sub-biseriate +  and uniseriate +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
orbicular +, oblong +  and flattened +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
persistent +  and caducous +
distinct +
spreading +, ascending +  and erect +
oblong +  and ovate +
reduced +
latiseptate +, schizocarpic +, samaroid +  and lomentaceous +
indehiscent +  and dehiscent +
angustiseptate +, flat +, angled +, terete +, torulose +, not +, segmented +  and nutletlike +
tetradynamous +
branched +  and unbranched +
procumbent +  and decumbent +
2 +  and 5 +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
Cruciferae +
Boechera pygmaea +
Boechera +
species +
branched +, short-stalked +  and simple +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.04 cm0.4 mm <br />4.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
perennial +  and long-lived +
erect +  and ascending +
glabrous +  and pubescent +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +
0.8mm;2mm +