Plants 1--8 cm, glossy yellowish green or golden green, not tomentose. Leaves 5--8 mm, erect when wet, appressed when dry, rarely falcate, narrowly lanceolate, ending in a long and fine, concolorous subula; alar cells conspicuous, hyaline, projecting into the costa; basal laminal cells hyaline, thin-walled, longly rectangular, lamina very short, ending at midleaf, distal laminal cells shortly rectangular or oblique, very small; costa very broad, occupying 3/4--4/5 of leaf width, longly excurrent in a fine almost entire subula, in transverse section showing very large, lax adaxial hyalocysts filling half of the costa thickness and no abaxial stereids, faintly ridged at back. Specialized asexual reproduction by deciduous leaves or broken leaf tips. Sporophyte not known.

Wet soil and soil covered rocks, wet cliffs in boggy slopes in subalpine habitats; B.C. (Queen Charlotte Islands and adjacent mainland); w Europe; e Asia .

Campylopus gracilis is easily recognized by a very broad costa, occupying 3/4 of the leaf width, very small shortly rectangular, distal laminal cells and large auricles projecting distinctly into the costa. In Europe, the species is found in similar situations in the highly oceanic parts as in the west coast of North America but also (as in C. atrovirens) in the Alps.