Leaves uniformly 3-lobed with angulate sinuses, longer than wide; oil bodies 2--7 per cell; gemmae brown to purplish, angulate; female bracts 3-lobed.

Exposed boulders, stream banks, soil on cliffs in forests, and seepage slopes in the tundra.; 500--1100 m; Greenland; Alta., B.C., Nfld. (Labrador), Nun., Que.; Alaska, Colo., Mont., Wash.; Europe; Asia.

It is frequently associated with Barbilophozia kunzeana, Blepharostoma trichophyllum, Calypogeia azurea, Cephalozia bicuspidata, Diplophyllum albicans, Harpanthus flotovianus, Jungermannia atrovirens, Leiocolea heterocolpos, Lophozia guttulata, L. incisa, Pleuroclada albescens, and Tritomaria exsectiformis.