Pterygoneurum subsessile var. subsessile
Capsule stegocarpous, spores released after operculum falls.
Spores mature late winter, spring. soil (sandy, volcanic), alkali flats; 600--1700 m; B.C., Alta., Sask., Yukon; Alaska, Ariz., Calif., Colo., Idaho, Ill., Iowa., Kans., Minn., Nebr., Nev., N.Mex., N.Dak., Okla., Oreg., S.Dak., Tex., Utah, Wyo.; s South America, Europe, Asia, n Africa.
