Isocoma acradenia var. eremophila

(Greene) G. L. Nesom
Phytologia 70: 82. 1991.
Illustrated
Basionym: Isocoma eremophila Greene Leafl. Bot. Observ. Crit. 1: 171. 1906
Synonyms: Haplopappus acradenius subsp. eremophilus (Greene) H. M. Hall Isocoma acradenia subsp. eremophila (Greene) R. M. Beauchamp
Treatment appears in FNA Volume 20. Treatment on page 441. Mentioned on page 440.

Leaf blades mostly 2.5–5 cm, margins pinnately toothed to pinnatifid. Involucres 6–8 m. Phyllary apices usually rounded, sometimes with weakly developed aristae. Florets 12–20. 2n = 12.


Phenology: Flowering (May–)Aug–Nov.
Habitat: Sandy soils, alkaline or salt flats, desert dunes, often with Saguaro-Prosopis-Larrea, Larrea, Atriplex, Yucca, or mixed shrubs
Elevation: (-15–)0–900(–1100) m

Distribution

V20-1009-distribution-map.gif

Ariz., Calif., Nev., Utah, Mexico (Baja California, Sonora).

Discussion

For the most part, var. eremophila is geographically separate from var. acradenia. In southwestern Nevada many intergrades occur; in San Bernadino County, California, the two taxa appear to be contiguous with little or no intergradation. In the latter area, the taxa apparently are at different ploidy levels.

Selected References

None.

Lower Taxa

None.

Guy L. Nesom +
(Greene) G. L. Nesom +
Isocoma eremophila +
Ariz. +, Calif. +, Nev. +, Utah +, Mexico (Baja California +  and Sonora). +
(-15–)0–900(–1100) m +
Sandy soils, alkaline or salt flats, desert dunes, often with Saguaro-Prosopis-Larrea, Larrea, Atriplex, Yucca, or mixed shrubs +
Flowering (May–)Aug–Nov. +
Illustrated +
Haplopappus acradenius subsp. eremophilus +  and Isocoma acradenia subsp. eremophila +
Isocoma acradenia var. eremophila +
Isocoma acradenia +
variety +