Groutiella Steere in Crum & Steere, Bryologist 53: 145. 1950.
Craspedophyllum Grout, N. Amer. Fl. 15A: 38. 1946, hom. illeg. non Copeland, 1938.
Micromitrium Schimp. ex Besch., Mém. Soc. Sci. Nat. Cherbourg 16: 190. 1872, hom. illeg. non Aust., 1870.
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 or 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 ¼ to _ the leaf length (rarely bordered by short-rectangular cells); costa strong, ending below the 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. Dioicous. Setae smooth, 1.5–15 mm long. Capsules 1–4 mm, oblong‑cylindrical or obovoid, smooth or furrowed; stomata superficial; opercula rostrate; peristome rudimentary, consisting of a low, papillose membrane. Spores isosporous or anisosporous. Calyptra mitrate‑campanulate, laciniate or plicate, naked or sparsely hairy.