Plants: 2–3.5 mm. Leaves: lingulate, lanceolate or ovate, 0.7–1.4 mm, margins recurved from near apex to near base, apex rounded or emarginate, piliferous; costa excurrent, with an abaxial epidermis, filaments of 1–4 cells, cells subspheric, with several papillae per cell, terminal cell subspheric; cells of leaf base 13–51 µm, medial and distal cells 11–20 µm, smooth, with 1–2 abaxial papillae or on either side in distal cells. Sexual: condition dioicous or cladautoicous. Seta: 8–16 mm. Capsule: urn ovoid-cylindric, 1.3–2 mm; operculum 0.5–1 mm; peristome strongly twisted, 650–980 µm. Spores: spheric, ovoid or oblong, finely papillose, 9–13 µm. Phenology: Capsule mature Jan–Jun(-Aug).
Soil and rocks under shrubs, shaded banks or in open sites in dry washes. moderate elevations (600-1500 m). Ariz., Calif., Colo., Nev., N.Mex., Tex., Utah, Mexico (Baja California, Sonora), n Africa.
Crossidium aberrans is easily distinguished by the smooth or 1-papillose cells of the distal leaf blade and by the low filaments with subglobose-papillose terminal cells.