Plants erect in green to brownish green tufts or turfs, to 1.5 cm high. Lower leaves not significantly reduced relative to upper ones. Leaves erect spreading to patent when moist, but, when dry, twisted in a tight spiral around the stem, concave, to 3 mm long, oblong ovate to obovate, 2–3: 1. Median laminal cells rather regularly short hexagonal, thin walled without corner thickenings, to 35 µm wide, 2–4: 1, smooth. Basal cells red to red brown, somewhat longer than median cells. Limbidium unistratose, comprised of up to 6 rows of linear, somewhat pale to reddish, rather thick-walled cells, only gradually differentiated from the adjacent laminal cells. Margins short decurrent, recurved above the middle, occasionally entire but usually somewhat serrulate distally. Costa short excurrent on at least some leaves of the clone, often forming a somewhat bleached and flexuose acumen. Costa cross section nearly homogeneous or with some differentiation of a median single layer of guide cells surrounded by a pair of substereid bands. Axillary hairs not offset from leaf insertion, to 5 cells long, to 350 µm, with one rather long basal brown cell. Rhizoids dense, especially near base of plant, sometimes originating from scattered nematogons, and sometimes inserted around poorly differentiated macronematal apparati, papillose, red-brown to almost red, to 25 pm in diameter at base, sparingly branched. Stem cross-section with a central strand, with leptodermous and hyaline inner corticals and with 1–2 layers of somewhat pachydermous, red brown outer cortical cells. Gemmiparous rhizoids often present in axils of upper leaves, papillose, red-brown, uniseriate, to 30 cells long, to 25 µm in diameter. Gemmae often also present on buried or surficial rhizoids within the substratum; these gemmae spherical to 400 µm in diameter, lightly papillose, pale to red brown.
Dioicous with male plants somewhat smaller than females. Perichaetia terminal with bracts markedly narrower and somewhat longer than adjacent vegetative leaves. Seta yellow to pale brown, smooth, erect, to 3 cm long. Urn yellow-brown to rather dark brown, to 5 mm long, 2–3: 1, pyriform to cylindric, symmetrical. Operculum conic to apiculate, much shorter than the urn. Annulus well-defined, revoluble. Exothecial cells at capsule mouth thick walled, to 50 µm broad, nearly isodiametric or somewhat transversely elongated, strongly differentiated in up to 6 rows. Exothecial cells at middle of urn irregularly rectangular, 2–5: 1, to 30 µm broad, rather thick walled, not in regular vertical rows. Stomata restricted to neck of capsule, phaneroporous, formed of two guard cells. Exostome teeth 16, pale to rather light yellow, to 600 µm long, finely and densely papillose striate below but papillose above, strongly trabeculate ventrally. Endostome segments about as long as the peristome teeth, with basal membrane comprising about 1/2 of their length, lightly papillose, keeled with perforations short oblong to circular. Cilia 2–3, strongly appendiculate. Calyptra cucullate, covering only the distal portion of the capsule. Spores light green, to 15 µm, smooth to finely papillose.
This plant is found on suitably moist, usually disturbed sites throughout the world. It is readily recognized when dry by the strong tendency of the leaves to twist around the stem. Its leaves are typically somewhat broader above the middle - - a somewhat unusual character in Bryum. Syed (1973) studied this species and its relatives on a world basis, and he emphasized the axillary gemmiparous rhizoids and the twisting of the dry plant in his recognition of a number of closely related species.
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