Plants minute, with shoots 1 4 × 0.3 0.5 mm, in small patches, light green to reddish brown or purplish, with numerous ventral stolon like branches bearing small leaves. Stems soft, 100 150 µm in diameter; branching ventral or lateral intercalary; rhizoids scattered along ventral stem, colorless. Leaves remote to contiguous, orbicular to oblong, slightly concave, 165 325 × 160 275 µm, entire to retuse or 2-lobed to 1/4, the lobes unequal with the dorsal smaller, lobe apices rounded, sinus obtuse; median leaf cells 15 24 × 14 16 µm, marginal cells smaller, 12 14 µm; cuticle smooth; walls slightly thickened, trigones small or absent; oil bodies 1 3 per cell, small, 3 10 µm, homogeneous. Underleaves subulate, occasionally with a lateral tooth, apparent only at stem apex. Sexual condition dioicous. Androecia terminal, becoming intercalary; bracts imbricate to julaceous, in 4 7 pairs, concave, 2-lobed, occasionally with a lateral tooth, wider than long, larger than leaves, ca. 250 × 270 µm, purplish; antheridia 1 2 per bract, stalk 2 seriate. Gynoecia on thick main stem or short branch with a fleshy rhizoidous perigynium at right angle to stem; bracts orbicular to reniform, concave; bracteole oblong to lanceolate; perianth conical, short, ca. 300 µm, hidden by bracts, mouth crenulate; perigynium fleshy, ca. 800 µm. Sporophyte capsule globose, brown; elaters 3 4 spiral. Spores 9 12 µm, slightly granulate.

Wet soil in snow melt, Arctic alpine; w Greenland; Alta., B.C., Wash.; Europe; Asia (Russia in Siberia; Japan).