Xanthisma spinulosum var. chihuahuanum

(B. L. Turner & R. L. Hartman) D. R. Morgan & R. L. Hartman

Sida 20: 1408. 2003.

Basionym: Machaeranthera pinnatifida var. chihuahuana B. L. Turner & R. L. Hartman Wrightia 5: 311. 1976
Synonyms: Haplopappus spinulosus var. chihuahuanus (B. L. Turner & R. L. Hartman) Gandhi
Treatment appears in FNA Volume 20. Treatment on page 392. Mentioned on page 391.
Revision as of 19:31, 16 December 2019 by FNA>Volume Importer

Perennials, 30–50 cm, often woody at base. Stems stiffly erect, usually much branched in proximal 1/2–2/3; mid internodes 2–5 mm. Leaves numerous, concentrated in proximal ± 1/2, spreading to loosely ascending, often much reduced distally, margins of proximal pinnatifid to 2-pinnatifid, of distal coarsely dentate to ± entire, lobes linear to lanceolate, 3–5 mm, faces usually hairy, rarely glabrous, often densely stipitate-glandular. Heads 2–10+ in diffuse arrays. Peduncles relatively terminal and lateral, 0.5–2 cm. Involucres 12–15 mm wide. 2n = 8, 16.


Phenology: Flowering spring–fall.
Habitat: Clayey to rocky washes, prairies, plains, roadsides
Elevation: 1000–1800 m

Distribution

V20-891-distribution-map.gif

Ariz., N.Mex., Tex., Mexico (Chihuahua, Coahuila, Durango, Sonora).

Discussion

Variety chihuahuanum is a Chihuahuan Desert taxon that extends into the southern United States.

Selected References

None.

Lower Taxa

None.
Ronald L. Hartman +
(B. L. Turner & R. L. Hartman) D. R. Morgan & R. L. Hartman +
Machaeranthera pinnatifida var. chihuahuana +
Ariz. +, N.Mex. +, Tex. +, Mexico (Chihuahua +, Coahuila +, Durango +  and Sonora). +
1000–1800 m +
Clayey to rocky washes, prairies, plains, roadsides +
Flowering spring–fall. +
Haplopappus spinulosus var. chihuahuanus +
Xanthisma spinulosum var. chihuahuanum +
Xanthisma spinulosum +
variety +