Chorizanthe sect. Acanthogonum

(Torrey) Torrey & A. Gray

Proc. Amer. Acad. Arts 8: 197. 1870.

Basionym: Undefined sect. Acanthogonum Torrey in War Department [U.S.], Pacif. Railr. Rep. 4(5): 132. 1857
Synonyms: Chorizanthe sect. Chorizanthella Parry
Treatment appears in FNA Volume 5. Treatment on page 466. Mentioned on page 446.

Plants prostrate to spreading or erect. Leaf blades oblanceolate to elliptic or round. Stems not disarticulating at each node. Inflorescences: bracts awned or awnless. Involucres cylindric, campanulate, or urceolate, not ventricose basally, 3-angled, 3-ribbed, 3-, 5-, or occasionally 6-toothed, without membranous or scarious margins; awns equal, sometimes anterior one longest. Flowers 1(–2); perianth white to rose or yellow, thinly to densely pubescent; stamens 3, 6, or 9; filaments adnate faucially at or near top of floral tube. Achenes brown to black, lenticular or 3-gonous.

Distribution

w United States, nw Mexico.

Discussion

Species 5 (5 in the flora).

G. J. Goodman (1934) assigned Chorizanthe polygonoides to Acanthogonum, which previously included C. rigida and C. corrugata (see below). J. L. Reveal and C. B. Hardham (1989b) considered that taxon to represent a section within Chorizanthe, expanded it further to include both C. orcuttiana and C. watsonii, and divided it into five subsections. Section Acanthogonum differs from sect. Ptelosepala by having involucral tubes that are not both 6-ribbed and 6-toothed at the same time.

Selected References

None.

James L. Reveal +
(Torrey) Torrey & A. Gray +
Undefined sect. Acanthogonum +
w United States +  and nw Mexico. +
Proc. Amer. Acad. Arts +
Chorizanthe sect. Chorizanthella +
Chorizanthe sect. Acanthogonum +
Chorizanthe subg. Amphietes +
section +