Plants delicate, scattered or in loose, yellowish to light green tufts, tomentose proximally. Stems usually simple, weakly erect to procumbent, 1--3 cm. Leaves erect when dry, somewhat distant, erect-spreading when moist, lanceolate from an ovate base, acuminate, 0.5--1.5 mm; margins plane to narrowly revolute, serrulate nearly to base, teeth single, projecting from distal ends of marginal cells; costa excurrent, rough abaxially distally; distal and median laminal cells oblong, 10--30 × 5--7 µm, prorulose at distal ends, basal cells shorter and broader, short-rectangular to quadrate, prorulose at distal or sometimes at proximal ends. Sexual condition dioicous; perigonia discoid. Seta 2--3 cm. Capsule 1.3--2 mm. Spores subreniform, 20--26 µm, papillose.

Capsules mature Apr.-- Aug. Moist sandy soil or humus, sometimes on rock ledges, often in shady habitats; 50--2300 m; B.C.; Alaska, Calif., Idaho, Oreg., Wash.; Europe; sw Asia.

Philonotis capillaris is distinguished by the unpaired teeth of the leaf margin that project from the distal ends of the cells and by the relatively short laminal cells with prorulae at the distal ends. In the flora area, the species is of restricted distribution, basically limited to Pacific coastal habitats from California to Alaska with incursions eastward to the western slopes of the Idaho Rockies. It is associated with an oceanic climate.