Plants very small, gregarious, half-buried in soil, dark green to olive-green. Stem not branching, ca 0.5-1 mm long, 140-170 µm in diameter, delicate, transverse section rounded, of thin-walled cells, central strand apparently absent, sclerodermis absent; axillary hairs of ca 3 uniseriate, hyaline cells; brown rhizoids common at stem base, the narrower12-17 µm in diameter mixed with wider 28-33 µm in diameter. Leaves deep, dark green, appressed and incurved when dry, reflexed at the base and wide-spreading when wet, short-to long-ovate or obovate, saccate, 0.3-0.5 mm in length, upper lamina broadly incurved throughout to fully clasping the bushy photosynthetic array; laminal margins incurved, weakly bordered by 1-2 rows of thinner-walled cells; leaf apex weakly but clearly cucullate in older and just maturing leaves, acute and entire in leaves at base of stem, leaf margins meeting distally just below the apex in an acute angle as a narrow notch or even somewhat over-folded, apex broadly rounded across cucullate portion, often umbonate by the weakly bulging costa curving over the cucullate apex; leaf base narrower than upper leaf or flaring outwards in older leaves and broadened; costa wide, ending shortly before the apex, weakly convex dorsally, bulging ventrally, dorsal superficial cells 6-7 rows wide, fusiform, ca 3-6:1, smooth, distalmost 3/5 to 4/5 of ventral surface of costa with dense mass of branching chlorophyllose filaments filling the enfolded laminal capsule; costa in transverse section ovate, dorsal epidermis absent, dorsal stereid band strong, hydroid strand weak, guide cells enlarged, 4-6across costa, filaments restricted to ventral surface of costa, 4-7 uniseriate cells in length, basally forming lamellae, terminal cells thick-walled and smooth grading to thin-walled, often with 1-2 simple papillae; upper laminal cells thick-walled, quadrate to rhombic or rectangular, 13-18 µm wide, 1-2(-3):1, superficially flat to very weakly convex, papillae absent; basal laminal cells weakly differentiated across base, quadrate, thin-to thick-walled, 11-14 µm wide, marginally often elongate and hyaline. Apparently dioicous, only archegoniate plants seen, perichaetial leaves little differentiated.
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