Clarkia williamsonii
Onagraceae tribe Onagreae
Fort miller clarkia, Fort miller clarkia or fairyfan
erect, to 100 cm, puberulent.
petiole 0–10 mm;
blade linear to narrowly lanceolate, 2–7 cm.
alternate or basal;
stipules absent.
open racemes, axis straight;
buds erect, mucronate.
floral tube 7–13 mm;
sepals reflexed individually or in pairs, tips distinct in bud;
corolla bowl-shaped, petals usually lavender, white near middle with purple spot distally, rarely uniformly wine-red, 10–30 mm;
stamens 8, subequal;
ovary 8-grooved, shorter than adjacent internode;
stigma usually exserted beyond anthers.
usually actinomorphic, rarely slightly zygomorphic (in Oenothera), (3 or)4-merous;
stamens 2 times as many, or rarely as many, as sepals;
pollen usually shed in monads, rarely tetrads (Chylismia sect. Lignothera).
a dry capsule, usually dehiscent, sometimes indehiscent.
10–30 mm.
brown or gray, 1–1.5 mm, scaly, crest 0.1 mm.
few to numerous, without hairs or wings, [very rarely with asymmetrical dry wing (Xylonagra)], or with dry (Oenothera), erose or smooth wing, or with thick, papillate wings (Chylismiella).
= 18.
Clarkia williamsonii
Onagraceae tribe Onagreae
Clarkia williamsonii occurs widely along the western slope of the Sierra Nevada from Nevada to Kern counties, and the Tehachapi Mountains barely to Los Angeles and Santa Barbara counties (one collection each). There are unverified reports from Riverside and Shasta counties.
Clarkia williamsonii is similar to C. speciosa and some populations of the hexaploid C. purpurea but can be distinguished from the former by petal color pattern and from both by having sepals that have distinctly free tips in bud, a trait most obvious in pressed specimens when the tips tend to spread apart.
(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.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
