Boechera falcifructa

(Rollins) Al-Shehbaz

Novon 13: 385. 2003.

Basionym: Arabis falcifructa Rollins Contr. Gray Herb. 212: 112. 1982
Treatment appears in FNA Volume 7. Treatment on page 377. Mentioned on page 358, 367.

Perennials; usually long-lived; apomictic; caudex often woody. Stems usually 1 per caudex branch, arising from center of rosette near ground surface, 1.5–4.5 dm, densely pubescent proximally, trichomes short-stalked, 4–9-rayed, 0.05–0.2 mm, glabrous or sparsely pubescent distally. Basal leaves: blade linear to narrowly oblanceolate, 1–4 mm wide, margins entire, ciliate at petiole base, trichomes (simple), to 0.5 mm, surfaces densely pubescent, trichomes short-stalked, 4–9-rayed, 0.05–0.2 mm. Cauline leaves: 5–9, not concealing stem; blade auricles 0.5–1 mm, surfaces of distalmost leaves sparsely pubescent. Racemes 10–18-flowered, sparingly branched. Fruiting pedicels divaricate-descending, gently curved downward, 6–12 mm, pubescent, trichomes appressed, branched. Flowers divaricate-ascending at anthesis; sepals pubescent; petals lavender, 5–7 × 0.7–1.2 mm, glabrous; pollen spheroid. Fruits divaricate-descending, not appressed to rachis, not secund, gently curved, edges parallel, 4.5–6 cm × 1.2–1.5 mm; valves glabrous; ovules 62–80 per ovary; style 0.5–1 mm. Seeds uniseriate, 1.2–1.7 × 0.8–1.2 mm; wing mostly distal, 0.05–0.1 mm wide.


Phenology: Flowering May–Jun.
Habitat: Rocky slopes and sandy soil in sagebrush or pinyon-juniper woodlands
Elevation: 1500-1800 m

Discussion

Of conservation concern.

Morphological evidence suggests that Boechera falcifructa is an apomictic species that arose through hybridization between B. cobrensis and B. fernaldiana. It is more similar to the former, but is distinguished by its gently curved fruiting pedicels (versus strongly recurved or reflexed distally), narrower (1.2–1.5 versus 1.7–2.5 mm) fruits, more (62–80 versus 34–64) ovules per ovary, longer (0.5–1 versus 0.05–0.2 mm) styles, and narrower (0.05–0.1 versus 0.25–0.5 mm) seed wings. Although independently reproducing, B. falcifructa is known only from Elko and Lander counties, where the parental species grow in proximity.

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 falcifructa"
oblong +  and ovate +
Ihsan A. Al-Shehbaz +  and Michael D. Windham +
(Rollins) Al-Shehbaz +
not +  and rosulate +
Arabis falcifructa +
appendaged +  and unappendaged +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
linear;narrowly oblanceolate +
much smaller +  and reduced +
1mm;4mm +
urceolate +, campanulate +  and tubular +
branched +  and simple +
petiolate +  and sessile +
well-developed +
indistinct +
not +  and differentiated +
emarginate +  and entire +
4.5 cm45 mm <br />0.045 m <br /> (6 cm60 mm <br />0.06 m <br />) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
1500-1800 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
actinomorphic +
divaricate-ascending +
divaricate-descending +
torulose +, falcate +, lanceolate +, oblong +  and linear +
Rocky slopes and sandy soil in sagebrush or pinyon-juniper woodlands +
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 +
Magenta (?) +, Red (?) +, Yellowish (?) +, Purple (?) +, Lavender (?) +, Pink (?) +  and White (?) +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
rudimentary +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
Flowering May–Jun. +
trinucleate +  and 3(-11)-colpate +
spheroid +
branched;10-18-flowered +
elongated +
reflexed +, ascending +  and erect +
slender +
mucilaginous +
margined +, not winged +  and winged +
biseriate +, sub-biseriate +  and uniseriate +
not +  and mucilaginous +
White (?) +, Black (?) +, Brown (?) +  and Yellow (?) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.17 cm1.7 mm <br />0.0017 m <br />) +
orbicular +, oblong +  and flattened +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 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 +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Cruciferae +
Boechera falcifructa +
Boechera +
species +
branched +  and short-stalked +
pubescent +  and glabrous +
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 +
perennial +  and long-lived +
downward +  and divaricate-descending +
0.6 cm6 mm <br />0.006 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
rhizomatous +, taprooted +, scapose +  and not +
perennial +, biennial +  and annual +
subshrub +  and herb +
aquatics +  and terrestrial +
glabrous +  and pubescent +
0.05mm;0.1mm +