Gametophyte. Monoicous. Female: innermost perichaetial leaf up to 2 mm long, sheathing, costa stout, percurrent, hair-point scarcely denticulate; male: perigonia in leaf axils or on short branches originating there, several on a stem, usually far from the perichaetium, innermost perigonial leaf 0.8 mm long, hyaline except the apical part, costa percurrent. Growth form: cushions adhering to the substrate by rhizoids or desintegrating, occasionally young shoots originating from the stem base, apices of the leaflets appressed to stem, plants erect, stems from 15 mm up to 70 mm high, branched by innovations, leaves arranged in tiers, stem with well-developed central strand. Leaves 1.5-2.5 mm long, densely set, in dry state appressed to stem, slightly turned, scarcely moving when moistened, erectopatent when wet, from elongate-ovate leaf base lanceolate, tapering to acute apex, hair-point weakly denticulate; leaf form in situ, at base concave, lower laminal part keeled, upper part narrowly so, margins weakly recurved on both sides from above leaf base to upper part of lamina, apical part of lamina plane; basal cells elongate-rectangular, walls thickened, weakly to strongly nodulose, variable from leaf to leaf on the same plant, near margin two or three rows of shorter cells with smooth walls appearing hyaline and differentiated from the elongated nodulose basal cells, in transitional part lamina cells narrow, elongate-rectangular with mostly strongly sinuose walls becoming shorter towards the margin, in apical part cells isodiametric or short-rectangular, walls thickened, more or less sinuose; leaf base, seen in transverse section, unistratose, lamina mostly unistratose throughout, in rare cases with bistratose patches, margins unistratose in leaf base and lower half of lamina, in upper part of lamina one to three marginal rows bi-or even tristratose. Costa, seen on dorsal side, of nearly uniform width, slightly thinner in leaf base, percurrent, costa, seen in transverse section, dorsally rounded, from above insertion to below apical part the costa being prominent, in laminal part exterior walls of dorsal cells markedly thickened, on ventral side in basal part widely channelled, in laminal part channelled, at insertion and at leaf base with 4 guide cells, in laminal part 2 guide cells, in mid-leaf small and elliptic in shape, mostly obliquely arranged to leaf axis, in leaf base and laminal part a centrally arranged group of hydroids or only one big star-shaped hydroid, vanishing in apical part, the dorsal costal cells with a small rounded lumen, transformed to substereids or stereids in the lower part of the leaf, in the prominent part of the costa a series of stereids arranged around the hydroids. Sporophyte. Seta to 2 mm long, arcuate or curved, vaginula 0.8 mm long, cylindrical. Capsule exserted, horizontal or slightly pendulose, obloid, ribbed, exothecial cells elongated, rectangular, penta-and hexagonal, walls thin, stomata numerous on short neck, annulus of 3 to 4 rows of cells detaching in fragments, cells at orifice of capsule with smooth, or rarely slightly crenulate outer walls. Calyptra mitrate, covering the upper third of capsule. Operculum conical with short beak, at rim some rows of cells with rounded lumina, in conical part rectangular or of irregular shape. Peristome teeth erect when dry, lanceolate, divided in the upper half into two divisions, the lower dorsal plates smooth, the subsequent plates with fine papillae, upper dorsal and ventral sides densely covered with rough papillae, trabeculae small to broad throughout, distant. Spores 11-15 µm, nearly smooth.
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