Authors: Steven Churchill

Stem leaves 3--3.5(--4) ´ 1--1.3 mm, margins multistratose throughout except 2-stratose at apex (pseudocosta in cross-section with chlorophyllose outer epidermal cells and small, thick-walled inner cells), toothed or entire; basa; laminal cells rectangular to quadrate, 15--40 ´ 7--10 µm, juxtacostal cells shorter; medial and distal laminal cells 10--15(--18) µm; marginal laminal cells with stereid cells 150--200 µm. Peristome lacking.

Exposed to submerged in streams or rivers, rocks, particularly granitic; 1000--1800 m; northwestern United States and extreme southwestern Canada, B.C.; Calif., Idaho, Mont., Oreg, Wash.