Plants very small, gregarious, light-green and commonly reddish. Stem not branching, ca 0.05-0.1 cm long, transverse section rounded-pentagonal, central strand apparently absent, central cylinder of large cells, cortex of several layers of orange cells with weakly thickened walls, sclerodermis and hyalodermis absent; axillary hairs ca 3-5 cells in length, basal cell brownish and more thick-walled than the distal cells; rhizoids common at stem base. Leaves appressed below and spreading when dry, often longitudinally broadly recurved on one side of leaf but incurved on other side of leaf so as to form an `S' in section, strongly transversely reflexed or squarrose when moist, ovate, 1.2-1.5 mm in length, upper lamina broadly channelled to weakly keeled, leaf margins plane throughout, distal laminal margins entire or serrulate by hollow papillae to occasionally distantly dentate above, often irregularly and weakly bordered in 1(-2) rows with somewhat thick-walled, less papillose cells, these often elongate 2:1; apex broadly acute and mucronate, base elliptical and sheathing stem; costa narrow but widening distally and bulging slightly on both sides near apex, excurrent as a broad, sharp or often rather blunt mucro of several cells, these smooth or papillose, or rarely percurrent, superficial cells elongate both ventrally and dorsally, papillose above midleaf, 3-4 rows of cells across costa ventrally at midleaf, transverse section circular to elliptical, essentially homogeneous or sometimes interpretable as stereid bands ventrally absent, dorsally present, of 3-4 stereid cells in 1-2 rows, ventral epidermis not or weakly differentiated, of cells of slightly wider lumens, guide cells 2 in 1 layer but little different from stereids, hydroid strand absent; upper laminal cells rounded-quadrate to irregularly rhomboid, ca 12-15(-18) µm in width, 1(-3):1, walls evenly thickened, strongly convex on both sides, papillae large but not crowded, 1-2 per lumen, simple or bifid, usually solid or sometimes hollow; basal cells differentiated across base, merging gradually into upper cells, near insertion short-rectangular and thin-walled, 17-25 µm wide, 2-4:1, grading distally into narrowly rectangular and thicker walled cells near leaf middle, these to 7:1. Paroicous. Perichaetia terminal, inner leaves enlarged and closely sheathing capsule, lower cells hyaline. Seta essentially absent. Capsule cleistocarpic, globose and bluntly short-apiculate, to 0.4 mm (immature) in diameter, transparent green, exothecial cells irregularly quadrate, 35-40 µm in diameter, walls thin, stomata apparently absent; annulus and peristome teeth absent. Calyptra mitrate, smooth, 350-370 µm in length. Spores 25-32 µm in diameter, weakly papillose (immature). Laminal KOH colour reaction orange.
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