Stephanomeria pauciflora
Stephanomeria malheurensis
brownplume wirelettuce, few-flower wirelettuce, prairie skeletonplant, wire-lettuce
Malheur wire lettuce
1–5+, divaricately and intricately branched (often forming dense bushes), usually glabrous, rarely tomentose.
single, branches ascending, glabrous.
withered at flowering;
basal blades linear-lanceolate, runcinate, 3–7 cm, margins pinnately lobed (faces glabrous);
cauline much reduced and bractlike.
withered at flowering;
basal blades oblanceolate to spatulate, 5–7 cm, margins entire to pinnately lobed (faces glabrous);
cauline much reduced, bractlike.
3–10 mm.
5–10 mm (glabrous).Calyculi of appressed bractlets.
8–11 mm (phyllaries 4–6, glabrous).
8–9.5 mm.
5–6.
5–6 (ligules usually pink, rarely white or orange-yellow).
of appressed bractlets.
borne singly along branches.
borne singly along branches.
tan, 3.5–5 mm, faces tuberculate, grooved;
pappi of 15–20, usually tan, rarely white, bristles (connate in groups of 2–4, bases persistent), plumose on distal 80%.
tan to light brown, 3.3–3.8 mm, faces moderately tuberculate, grooved;
pappi of 9–12(–15), light tan bristles (connate in groups of 2–4, bristles and/or bases persistent), plumose on distal 50–60%.
= 16.
= 16.
Stephanomeria pauciflora
Stephanomeria malheurensis
Stephanomeria pauciflora generally grows as an intricately branched, often rounded bush. Occasional plants, usually from Arizona, New Mexico, Texas, and southern Utah, have long, flexuous stems and branches, an architecture that resembles one of the typical forms of S. tenuifolia. Some plants of S. pauciflora have white pappi, also typical of S. tenuifolia. It is not known if these plants represent uncommon and unusual individuals or if they are from populations in which all plants have those traits. It is also not known whether such plants of S. pauciflora grow near populations of S. tenuifolia; if so, they may result from interspecific hybridization. That is a possibility; experimental hybrid plants produced by crossing individuals from the two species were about 20% fertile. Such fertility suggests the species are sufficiently compatible that fully fertile segregants with variously intermediate morphologies could be expected where they hybridize in nature. The experimental crosses were made reciprocally between S. pauciflora from Riverside County, California (L. D. Gottlieb 6653), and S. tenuifolia from Wheeler County, Oregon (L. D. Gottlieb 6692); specimens of the six F1 hybrid plants that were produced are deposited at DAV. Plants of S. pauciflora that are densely tomentose throughout are occasionally found, particularly in the deserts of California and Nevada, and have been named S. cinerea or S. pauciflora var. parishii.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Of conservation concern.
Stephanomeria malheurensis has been examined in a series of studies (L. D. Gottlieb 1973b, 1977, 1978b, 1979, 1991; Gottlieb and J. P. Bennett 1983; S. Brauner and Gottlieb 1987, 1989; B. A. Bohm and Gottlieb 1989) because it is one of the very few examples of the recent, natural origin of a diploid, annual plant species. At the type locality, it grows with a population of S. exigua subsp. coronaria that is thought to be its progenitor.
Stephanomeria malheurensis is known from a single locality in Harney County, Oregon, growing in soil derived from volcanic tuff in the high desert of eastern Oregon. It is a federally listed rare and endangered species, and is in the Center for Plant Conservation’s National Collection of Endangered Plants.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
KS Wildflowers
SW CO Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
OR
Flora NW
PNW Herbaria
