Plants in very dense mats, green to yellowish or olive-green. Stems to 8 cm long, prostrate, irregularly branched and markedly julaceous with branches ascending from the base but mostly curled down toward the substratum. Leaves of stems and branches similar, to 2 mm, 1.5–2.5: 1, symmetric, oblong-ovate to elliptic, widest near middle, blunt and mostly obtuse at apex but a few leaves with abrupt acumina to 0.5 mm long, concave, densely imbricated, not much changed on drying. Margins mostly minutely recurved near insertion but sometimes nearly plane, neither decurrent nor cordate at base, nearly entire below the middle but serrulate to serrate distally. Median cells smooth, to 6 µm wide, linear-vermiculate, 10–20: 1, rather thin-walled. Alar cells undifferentiated or few and quadrate to short rectangular, thin-walled, only gradually differentiated from adjacent laminal cells. Basal cells well-demarcated in 1–3 rows, rectangular. 2–3: 1, thin-walled and translucent. Differentiated basal cells cloaking base of costa. One or a group of apical cells rhomboidal, 1–3: 1. Costa extending about 3/4–7/8, usually ending in one or several abaxial spines. Pseudoparaphyllia lanceolate, sharply dentate and acuminate, to 100 µm long. Axillary hairs 4-celled, to 50 µm with 2 basal brown cells, not offset from leaf insertion. Rhizoids red-brown, sparingly branched, to 15 µm at insertion, smooth, in scattered but dense fascicles on ventral surface of stem, especially near branch insertion.
Dioicous with male plants similar to females. Perichaetia on stoloniferous axis or on bases of branch axes, to 2.5 mm long. Perichaetial bracts ecostate, abruptly acuminate with divergent acumens from an ovate-lanceolate base; cells to 25:1, with straight lateral walls. Seta to 1.5 cm long, red-brown, smooth below but lightly papillose and geniculate at apex. Capsule brown but dark at base, strongly strangulate. Urn to 2 mm, 3–5: 1. Exothecial cells at middle of urn in more or less regular rows, to 25 µm wide, 2–3: 1, with thin but collenchymatous red-brown walls. Exothecial cells near mouth of capsule shorter and thicker walled than median exothecial cells, not in a well-demarcated band. Stomata numerous, phaneroporous, restricted to base of capsule. Operculum conic to short-rostrate, about 1/2 as long as urn. Exostome to 500 µm long, horizontally striate below, papillose above, red-brown, strongly trabeculate ventrally. Endostome segments low papillose, open on keel, about as long as exostome with basal membrane about as high as the segments. Cilia 2–3, somewhat appendiculate. Spores smooth to inconspicuously papillose, 15–18 µm.
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