Plants uniformly strongly brownish. Leaf cells 24--26 ´ 30--45 m m in midleaf, trigones coarse and bulging; oil bodies 5--15 per cell.

Arctic and sub-Arctic fens, bogs, and on hillsides. It is frequently associated with Antheria juratzkana, Barbilophozia binsteadii, B. kunzeana, Blepharostoma trichophyllum subsp. brevirete, Cephaloziella arctica, Lophozia ventricosa, and Odontoschisma macounii; 0--3400 m; e and nw Greenland; Yukon; Alaska; Asia (Siberia).

The plants grow to 4 mm in width and the perianth is strongly ciliate-dentate with teeth 4--6 cells long, and 2--4-stratose at base in contrast to 1--3-stratose in subsp. quinquedentata.