Flora 2: 301. 1819,.
Stems 2–10 mm. Leaves infolded and twisted when dry, erect-spreading when moist, lingulate or spatulate, 1.5–3 × 0.5–1.5 mm; margins revolute in the proximal 1/2, entire; apices broadly acute or obtuse, sometimes emarginate; costa excurrent into a short, serrate, hyaline awn, brown or red, often papillose abaxially and serrulate near the apex because of projecting cell ends; basal-cells abruptly differentiated, narrower toward the margins; distal cells polygonal or quadrate, 8–12 µm, with 4–6 papillae per cell. Specialized asexual reproduction absent. Sexual condition dioicous. Seta red, 8–14 mm. Capsule red, 2–3.5 mm, straight or slightly curved; operculum 1.2–2 mm, red; peristome 0.5–1.3 mm, the basal membrane to 1/2 the total length, red. Spores 10–13 µm, papillose.
Habitat: Widespread on soil and rock, occasionally on tree bark
Elevation: moderate to high elevations
Alta., B.C., Ariz., Calif., Idaho, Maine, Mont., Nev., N.Mex., N.Y., Oreg., Wash., Europe, Asia
This treatment follows M. T. Gallego et al. (2006) in employing Syntrichia montana to encompass what has been called S. intermedia or S. ruralis var. crinita in North America. This is, however, a tentative decision as there remains an incompletely understood complex of small, dioicous plants with hydroids in the costa, and some currently undescribed taxa may yet need to be recognized. One recently described species that falls in this complex is S. rupicola B. H. Allen. Further field sampling, molecular characterization, and culture studies are necessary before these taxa are fully understood.