Plants slender, pale green to dull green, occasionally yellowish green, 2--6 cm, irregularly to somewhat pinnately branched, some branches frequently filiform. Leaves subjulaceous, straight to somewhat falcate, gradually narrowed to slender acumen, nearly entire, alar cells subquadrate, usually in a well-defined group. Sporophytes unknown in North America, rare in the entire range.

Mainly confined to perpendicular surfaces of cliffs and tree-trunks; 0--2500 m; N.B., N.S., P.E.I.; Ark., Conn., Maine, Mass., Mich., N.H., N.J., N.Y., N.C., Okla., Pa., Tenn., Tex., Va; South America (Chile); Europe; Asia; Africa; Pacific Islands (New Zealand); Australia.

When well developed, Hypnum cupressiforme var. filiforme is distinctive, with filiform julaceous stems and straight leaves. There are variants with somewhat falcate-secund leaves that can be confused with H. andoi. The latter species rather has long-attenuate leaf apices, is not julaceous, although filiform, and the leaves are not strongly imbricate as in var. filiforme. The many specimens that closely resemble var. filiforme strongly suggest that it may be an environmental form induced by the habitat that holds moisture rather briefly during the growing season.