Boechera languida

(Rollins) Windham & Al-Shehbaz

Harvard Pap. Bot. 12: 244. 2007.

Basionym: Arabis demissa var. languida Rollins Rhodora 43: 388. 1941
Synonyms: Boechera demissa var. languida (Rollins) Dorn
Treatment appears in FNA Volume 7. Treatment on page 387. Mentioned on page 358, 359.
Revision as of 23:58, 27 May 2020 by imported>Volume Importer

Perennials; short- to long-lived; apomictic; caudex usually not, or, rarely, woody. Stems usually 2–5 per caudex branch, arising from margin of rosette near ground surface, or arising laterally proximal to sterile shoots, 1–3 dm, pubescent proximally, trichomes simple, to 1 mm, mixed with short-stalked, 2-rayed ones, 0.15–0.5 mm, glabrous or sparsely pubescent distally. Basal leaves: blade linear-oblanceolate to oblanceolate, 1–5(–9) mm wide, margins entire, ciliate, trichomes (simple), to 1 mm, surfaces densely pubescent, trichomes simple and 2–4-rayed, 0.15–0.5 mm. Cauline leaves: 3–7, not concealing stem; blade auricles 0.5–1.5 mm, surfaces of distalmost leaves sparsely pubescent or glabrous. Racemes 10–20-flowered, usually unbranched. Fruiting pedicels horizontal, slightly to strongly recurved near apex, 3–13 mm, glabrous or, rarely, with simple trichomes. Flowers divaricate-ascending at anthesis; sepals pubescent; petals white to pale lavender, 4–6 × 1.5–2 mm, glabrous; pollen spheroid. Fruits pendent, not appressed to rachis, not secund, straight to slightly curved, edges parallel, 3–4.5 cm × 1.8–2 mm; valves glabrous; ovules 42–70 per ovary; style 0.1–0.3 mm. Seeds sub-biseriate, 1.2–1.5 × 0.8–1 mm; wing absent or distal, 0.05–0.12 mm wide.


Phenology: Flowering May–Jun.
Habitat: Rocky slopes in sagebrush and pinyon-juniper communities
Elevation: 1800-2300 m

Discussion

Boechera languida is an apomictic hybrid that is often subsumed under Arabis demissa (= B. oxylobula). Morphological evidence suggests a closer relationship to B. spatifolia, which probably is one of its parents (see M. D. Windham and I. A. Al-Shehbaz 2007b for detailed comparison).

Selected References

None.

Lower Taxa

None.