Androsace occidentalis

Pursh

Fl. Amer. Sept. 1: 137. 1813 ,.

Common names: Western rock jasmine
IllustratedEndemic
Synonyms: Androsace arizonica A. Gray Androsace occidentalis var. arizonica (A. Gray) H. St. John. Androsace occidentalis var. simplex (Rydberg) H. St. John Androsace platysepala
Treatment appears in FNA Volume 8. Treatment on page 262. Mentioned on page 260.

Plants annual, inconspicuous, not mat-forming. Leaves in single rosette; petiole obscure; blade lanceolate, oblanceolate, or spatulate, 5–30 × 4–9 mm, base obscurely narrowing to stem, margins with simple hairs, surfaces puberulent, hairs simple. Scapes 1–15, 2–10 cm, glabrescent to puberulent. Inflorescences 3–15-flowered; involucral-bracts lanceolate to elliptic or ovate, relatively broad. Pedicels erect to arcuate, slender, unequal, 0.3–3 cm. Flowers: calyx broadly campanulate, ridged, 3–5 mm, lobes erect, broadly lanceolate, apex acute to obtuse; corolla-tube equaling or shorter than calyx, limb ca. 3 mm diam. Capsules ± equaling calyx, 3–5 mm. 2n = 20.


Phenology: Flowering early-mid summer.
Habitat: Open, grassy meadows, sandy or gravelly open soils, often in disturbed areas
Elevation: 300-1700 m

Distribution

V8 536-distribution-map.gif

Alta., B.C., Man., Ont., Sask., Ariz., Ark., Calif., Colo., Idaho, Ill., Ind., Iowa, Kans., La., Mass., Mich., Minn., Mo., Mont., Nebr., N.Mex., N.Dak., Ohio, Okla., S.Dak., Tex., Utah, Wis., Wyo.

Discussion

Androsace occidentalis is widespread across the central and western United States, extending into southern Canada. It is often confused with A. septentrionalis, with which it overlaps geographically somewhat in the western portion of its range. Androsace occidentalis is generally restricted to lower elevations and is distinguished by its broad involucral bracts and cup-shaped calyx. In A. septentrionalis, the involucral bracts are narrow and the calyx V-shaped at the base, a shape enhanced by the more prominent calyx ridges. Hybridization between A. occidentalis and A. septentrionalis has not been documented; some specimens from intermediate elevations in the Four Corners area show intermediate bract morphology and slight glandular pubescence, a characteristic of some southwestern populations of A. septentrionalis.

Selected References

None.

Lower Taxa

None.
... more about "Androsace occidentalis"
not connivent +
emarginate;entire +
Sylvia Kelso +
multiple +  and single +
cuneate +  and attenuate +
narrowing +
0.5 cm5 mm <br />0.005 m <br /> (3 cm30 mm <br />0.03 m <br />) +
crenulate +  and denticulate +
spatulate;oblanceolate;spatulate;oblanceolate;lanceolate +
4mm;9mm +
1 (?) +  and 10 (?) +
puberulent +, pilose +  and glabrous +
ridged +  and campanulate +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
globose +  and subglobose +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Western rock jasmine +
Alta. +, B.C. +, Man. +, Ont. +, Sask. +, Ariz. +, Ark. +, Calif. +, Colo. +, Idaho +, Ill. +, Ind. +, Iowa +, Kans. +, La. +, Mass. +, Mich. +, Minn. +, Mo. +, Mont. +, Nebr. +, N.Mex. +, N.Dak. +, Ohio +, Okla. +, S.Dak. +, Tex. +, Utah +, Wis. +  and Wyo. +
300-1700 m +
operculate +  and capsular +
Open, grassy meadows, sandy or gravelly open soils, often in disturbed areas +
grayish white +
nectariferous +
involucrate +  and 2-20-flowered +
3 cm30 mm <br />0.03 m <br /> (?) +
lanceolate +
dentate +  and entire +
tenuinucellate +  and bitegmic +
elongating +
unequal +  and slender +
0.3 cm3 mm <br />0.003 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Flowering early-mid summer. +
Fl. Amer. Sept. +
glabrescent +  and puberulent +
2 cm20 mm <br />0.02 m <br /> (10 cm100 mm <br />0.1 m <br />) +
reticulate to almost +
trigonous +  and 4-angled to somewhat +
Illustrated +  and Endemic +
connate +  and distinct +
inflated +
Androsace arizonica +, Androsace occidentalis var. arizonica +, Androsace occidentalis var. simplex +  and Androsace platysepala +
Androsace occidentalis +
Androsace +
species +
inflated +
stoloniferous +  and rhizomatous +
plant +  and not mat-forming +