John C. Semple WAT

Herrickia Wooten & Standley

GREAT BASIN EURYBIOID ASTERS

Herrickia Wooten & Standley is small North American genus native to the Great Basin intermountain region of the western United States. All members have 2n = 18 (x=9). The generic status was generally not accepted and has only recently been expanded and reinstated. Brouillet, Urbatsch & Roberts (2004, Sida 21: 889-900.) presented the results of a NRDNA sequence analysis that sorted out the relationships among species at the base of the Machaerantherinae-Symphyotrichinae Clade. Oreostemma, Herrickia, Eurybia and Triniteurybia formed a grade of genera leading to the Machaerantherinae genera with lower base numbers of x = 6, 5 and 4 (e.g., Machaeranthera sensu Morgan and Hartman (2003 Sida 20:1287-1416.), Xanthisma sensu Morgan and Hartman (2003), Isocoma, Haplopappus, Lessingia, etc.).

As originally proposed by Wooten and Standley (1913) Herrickia included just H. horrida, which has sharply toothed-spinulose leaves similar to those of many Machaerantherinae taxa. Nesom (1994) included the genus as a section within Eurybia and added Eucephalus glauca and Eucephalus wasatchensis to it. Brouillet et al. (2001) and Semple et al. (2002) indicated that the phylogeny of Eurybia sensu Nesom was unresolved. Brouillet et al. (2004) clarified the phylogeny of the eurybioid asters.

Herrickia horrida

Herrickia glauca (Aster glaucodes)

var. glauca habit, shoot, involucre, Utah
var. pulchra

Herrickia wasatchensis; habit, heads, involucre, Utah

Herrickia kingii

var. kingii
var. barnebyana