Description: Extremely small herbaceous moss, forming dense, hoary tufts that rarely exceed 6 mm (0.24 in.) in height. Leaves piliferous (bearing hairs); and under a microscope, the upper leaf surface has distinctive costal (midrib) photosynthetic filaments which are partially fused into short lamellae, the terminal cell of these filaments being nearly globose. Additionally, the median cells of the leaf are mostly unipapillose with several C-shaped papillae. Capsules oblong-cylindrical, or oblong-elliptic, erect, straight or slightly curved, peristome (fringe of teeth) of 32 hair-like divisions. These “teeth” are nearly erect and spirally twisted. This species is bisexual, but does not normally produce fruit.
Habitat: Restricted to sandstone and gypsum soils within the creosote-bursage community; on bluffs, outcrops, rock piles, and in protected areas on north or east side of rocks or shrubs, or at bases of bluffs. Grows in clumps on exposed soils or in shadow of shrubs like Mormon tea (Ephedra). Elevations: 400 - 750 m (1,312 - 2,460 ft).
Range: Locally known from a few areas around Lake Mead, Clark County, Nevada. Also known from Arizona, California, Baja California (Mexico), and Spain. Globally rare, known from less than ten populations, with possibly the most numerous in Nevada.