Pterostegia
Pterostegia drymarioides
pterostegia, woodland threadstem
fairy mist, woodland pterostegia, woodland threadstem
arising directly from the root, sprawling and spreading, solid, not fistulose or disarticulating into ringlike segments, thinly pubescent.
persistent, cauline, opposite;
petiole present;
blade broadly elliptic to fan-shaped, margins entire or lobed.
petiole 0.2–0.6(–1) cm;
blade 0.3–2 × 0.5–2.5(–3) cm.
terminal, cymose, uniparous due to suppression of secondaries distally;
branches dichotomous, not brittle or disarticulating into segments, round, thinly pubescent;
bracts absent.
absent.
2–3 per involucral cluster;
perianth pale yellow to pink or rose, campanulate when open, urceolate when closed, sparsely pubescent abaxially;
tepals (5–)6, connate for ca. 1/3 their length, monomorphic, entire apically;
stamens 6;
filaments adnate to perianth, glabrous;
anthers yellow, oval.
perianth 0.9–1.2 mm;
filaments 0.5–0.6 mm;
anthers 0.2–0.3 mm.
included, yellowish brown to brown, winged, globose, glabrous.
1.2–1.5 mm.
embryo straight.
bracts 1, erect, 2-winged, reticulately veined, lobed or notched, slightly gibbous with age, invaginated adaxial surface hyaline.
bracts 1–1.5(–3) × (1.5–)2-3(–3.5) mm.
= 14.
= 28.
Pterostegia
Pterostegia drymarioides
Species 1.
Pterostegia and the Baja California, Mexico, endemic Harfordia are the only genera of the tribe Pterostegieae. In both, the involucre is highly modified, becoming a slightly to markedly gibbous, reticulated, winged structure that encloses the mature achene. In Pterostegia, the two wings are slightly enlarged, but in Harfordia the wings are greatly inflated, which apparently aids in achene dispersal.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
The only presumed Oregon collection of Pterostegia drymarioides (Tolmie s.n., GH) was gathered along the Columbia River sometime in the 1830s. The only collection reportedly from New Mexico (Parry et al. 1171, US) supposedly was found in the Rio Grande Valley in the 1850s during the United States-Mexico Boundary Survey. The species likely will be found in southern Oregon (not northern), but it is unlikely that it ever occurred in New Mexico. A problem is that this species is often difficult to notice, as the plants tend to be in the shade under shrubs. Specimens often are misidentified as Parietaria (Urticaceae)—See Flora of North America volume 3, pages 406–408.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
