Flora of North America species comparison

The distribution of subsp. pallida centers in the intermountain region from Oregon and Washington east of the mountains, adjacent southern British Columbia, south through southern Idaho, Wyoming, western half of Utah, southern Nevada, to northern Arizona, northwestern New Mexico, and adjacent southwestern Colorado. There are morphological intermediates with subspp. runcinata and trichocalyx. Densely strigillose plants occur within the range of subsp. pallida, especially near the St. Anthony Dunes in Idaho, and have been referred to as var. idahoensis.

Baumannia douglasiana Spach is an illegitimate name that pertains here.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Genera 13, species 265 (12 genera, 199 species in the flora).

Onagreae account for more than half the total genera in Onagraceae and diversified from a center in southwestern North America (L. Katinas et al. 2004). Delimitation of the tribe by W. L. Wagner et al. (2007) differs from previous ones by the exclusion of Gongylocarpus, now in its own tribe, by the segregation of eight genera (Camissoniopsis, Chylismia, Chylismiella, Eremothera, Eulobus, Neoholmgrenia, Taraxia, and Tetrapteron) from Camissonia, and by the inclusion of three previously separate genera (Calylophus, Gaura, and Stenosiphon) in Oenothera. Within the branch of the family that lacks stipules (Gongylocarpeae, Epilobieae, and Onagreae), the last two tribes form a clade that has very strong molecular support (R. A. Levin et al. 2003, 2004), but no obvious morphological synapomorphy. The clade may be defined by a cytogenetic change from the base chromosome number of x = 11 found in Circaeeae, Gongylocarpeae, and Lopezieae, to x = 18 in Epilobieae, and x = 7 in Onagreae; however, these changes could also have occurred independently. Other than the new chromosome number x = 7, the only apparent morphological synapomorphy for Onagreae alone is pollen with prominent apertural protrusions (J. Praglowski et al. 1987, 1989), a character state also found in Circaeeae (Praglowski et al. 1994). The monophyly of Onagreae has moderate (Levin et al. 2004) to strong support (V. S. Ford and L. D. Gottlieb 2007).

(Discussion copyrighted by Flora of North America; reprinted with permission.)