Orthotrichaceae

Diagnosis: Plants slender to medium-sized, in dark-green, yellow-green, reddish-green, reddish-brown to olive-brown, tomentose mats or cushions. Primary stems creeping, secondary stems erect-ascending, irregularly branched. Leaves contorted, spirally twisted, crisped to rugose when dry, erect-spreading to wide-spreading when wet, keeled, linear-lanceolate, lanceolate, oblong- to ovate-lanceolate or lingulate; apices obtuse, acute, acuminate, mucronate, sometimes with fragile tips; margins entire above, entire to serrulate at base, bordered at base by several rows of narrow, elongate cells from 1/4 to 2/3 the leaf length; costa strong, ending below apex, percurrent or excurrent; cells incrassate, upper cells rounded-hexagonal, smooth to mammillose, basal cells rounded-rectangular, smooth or rarely with a few tubercula, those near the costa somewhat enlarged and thin-walled, at times with enlarged basal teeth at leaf insertion. Seta smooth; capsules oblong-cylindrical or obovoid, smooth or furrowed; operculum rostrate; peristome rudimentary, consisting of a low, papillose membrane. Calyptra mitrate-campanulate, laciniate or plicate, naked or sparsely hairy. Spores isosporous or anisosporous.