Plants terrestrial or on rock. Stems compact or short-creeping, horizontal, solenostelic (having phloem on both sides of xylem) or dictyostelic (having complex nets of xylem), clothed with orange to reddish brown hairs. Leaves erect [rarely forming a flat rosette], partially to entirely dimorphic. Sporangia in 2 rows on ultimate segments of fertile pinnae, sessile, oblong; annulus apical. Spores tetrahedral-globose, with parallel or rarely anastomosing ridges. Gametophytes terrestrial, green, cordate with unequal lobes.