Boechera falcatoria

(Rollins) Dorn

Brittonia 55: 3. 2003.

Basionym: Arabis falcatoria Rollins Contr. Gray Herb. 212: 106. 1982
Treatment appears in FNA Volume 7. Treatment on page 376. Mentioned on page 363, 377.

Perennials; short to long-lived; apomictic; caudex sometimes woody. Stems usually 2–7 per caudex branch, arising from margin of rosette near ground surface, 0.5–2 (–3) dm, densely pubescent proximally, trichomes simple and stalked, 2-rayed, 0.3–0.8 mm, glabrous distally. Basal leaves: blade narrowly oblanceolate, 1–3 mm wide, margins entire, ciliate, trichomes to 1 mm, surfaces pubescent, trichomes stalked, 2–4-rayed, 0.3–0.8 mm. Cauline leaves: 3–7 (–10), not concealing stem; blade auricles 0.2–1 mm, surfaces of distalmost leaves glabrous. Racemes 6–15-flowered, unbranched. Fruiting pedicels horizontal to divaricate-ascending, straight, 3–9 mm, glabrous. Flowers ascending at anthesis; sepals pubescent; petals white or lavender, 5–7 × 1.5–2.5 mm, glabrous; pollen spheroid. Fruits horizontal to divaricate-ascending, not appressed to rachis, not secund, usually strongly curved, edges parallel, 3.5–6.5 cm × 1.7–2 mm; valves glabrous; ovules 50–84 per ovary; style 0.05–0.5 mm. Seeds uniseriate, 1.5–2 × 1.1–1.5 mm; wing continuous, 0.1–0.2 mm wide.


Phenology: Flowering May–Jun.
Habitat: Rock outcrops and gravelly soil in sagebrush and mountain shrub communities
Elevation: 2000-2200 m

Discussion

Of conservation concern.

Although the exact parentage of Boechera falcatoria, an apomictic hybrid, remains in doubt, it is virtually certain that B. cusickii contributed at least one genome. Boechera falcatoria has been confused with both B. pendulina and B. perennans, but is amply distinct from both (see M. D. Windham and I. A. Al-Shehbaz 2007 for detailed comparison). Despite the proximity of the type locality to both Idaho and Nevada, the species is known only from northwestern Box Elder County.

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 falcatoria"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +  and Michael D. Windham +
(Rollins) Dorn +
not +  and rosulate +
Arabis falcatoria +
appendaged +  and unappendaged +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
oblanceolate +
much smaller +  and reduced +
1mm;3mm +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and sessile +
well-developed +
indistinct +
not +  and differentiated +
emarginate +  and entire +
3.5 cm35 mm <br />0.035 m <br /> (6.5 cm65 mm <br />0.065 m <br />) +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
2000-2200 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
horizontal +  and divaricate-ascending +
torulose +, falcate +, lanceolate +, oblong +  and linear +
Rock outcrops and gravelly soil in sagebrush and mountain shrub communities +
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 +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
rudimentary +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Flowering May–Jun. +
trinucleate +  and 3(-11)-colpate +
spheroid +
unbranched;6-15-flowered +
elongated +
horizontal +  and divaricate-ascending +
slender +
0.3 cm3 mm <br />0.003 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
mucilaginous +
margined +, not winged +  and winged +
biseriate +, sub-biseriate +  and uniseriate +
not +  and mucilaginous +
White (?) +, Black (?) +, Brown (?) +  and Yellow (?) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
orbicular +, oblong +  and flattened +
0.11 cm1.1 mm <br />0.0011 m <br /> (0.15 cm1.5 mm <br />0.0015 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 7 +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.005 cm0.05 mm <br />5.0e-5 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
glabrous +  and pubescent +
Cruciferae +
Boechera falcatoria +
Boechera +
species +
stalked +  and simple +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
coiled +, 1-7-veined +  and veined +
anastomosing +
perennial +  and long-lived +
hispid +, hirsute +, pubescent +  and glabrous +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +
0.1mm;0.2mm +