Plants with shoots 10 30 × 2 2.5 mm. Leaves circular to reniform in outline, up to 1.2 × 1.4 mm with some leaves emarginate, the indentation sharp, the lobes broadly rounded; median leaf cells 30 40 × 28 32 µm, marginal cells 28 38 µm, oil bodies 2 3( 6) per cell, ovoid to ellipsoid, 10 16 × 6 9 µm, granular botryoidal, made up of numerous small droplets, opaque.

Soil over rock with seepage or on peat in bogs; w Greenland; N.S.; Tenn. (Great Smoky Mountains).

Fertile plants often have reddish undersides, especially near the bulbous perigynium and around the base of rhizoids. Both subspecies are found in Tennessee above 1520 m in Spruce Fir forests.