Plants small to medium-sized. Leaves straight, 1.2-1.5(-1.7) mm; laminal cells elongate, 30- 60 µm.

Soil, rock, mountains; high elevations (3100-3200 m); Colo., Wyo.

Variety alpinum has strongly plicate and concave leaves, julaceous foliage, and numerous alar cells. These alpine plants from the Rocky Mountains resemble Brachythecium coruscum rather than B. erythrorrhizon var. erythrorrhizon, but differ in larger cells in alar regions and leaf decurrencies (Y. Kosovich-Anderson and M. S. Ignatov 2010).