Isocoma acradenia var. bracteosa

(Greene) G. L. Nesom
Phytologia 70: 81. 1991.
Endemic
Basionym: Isocoma bracteosa Greene Leafl. Bot. Observ. Crit. 1: 170. 1906
Synonyms: Haplopappus acradenius subsp. bracteosus (Greene) H. M. Hall
Treatment appears in FNA Volume 20. Treatment on page 441. Mentioned on page 440.

Leaf blades mostly 50–150 mm, margins of proximal usually shallowly toothed, of distal entire or serrulate. Involucres 7–8 mm. Phyllary apices spinulose-aristate. Florets 20–27. 2n = 12.


Phenology: Flowering Aug–Oct.
Habitat: Salt flats
Elevation: 0–20 m

Discussion

In the limited zone of contact between vars. bracteosa and acradenia, intermediates are rare. The two differ in chromosome number and significantly in habitat (altitudes are essentially non-overlapping). Field studies may show them to warrant distinction at specific rank.

Selected References

None.

Lower Taxa

None.