Stems short- to long-creeping, individual branches usually 3--5 mm diam. Blade finely cut, 2-pinnate-pinnatifid. Proximal pinnules of lower pinnae usually deeply lobed or pinnatifid. Spores averaging 35--42 µm. 2 n = 76.

Sporulating summer--fall. Cliffs and rocky slopes (rarely terrestrial); found on a variety of substrates but mostly sandstone and granite; 200--500 m; Ark., Kans., Mo., Okla., Tex.

Woodsia obtusa subsp. occidentalis hybridizes with subsp. obtusa sporadically throughout the region of sympatry; the hybrids are sterile triploids with malformed spores.