Plants: medium-sized to large, in moderately loose mats, green to golden green. Stems: to 5 cm, leafy shoots 0.8–1.2 mm wide, branches julaceous. Stem: leaves closely imbricate, ovate to ovate-lanceolate, 1–2 × 0.5–1.2 mm; margins often widely incurved distally, entire or with serrulations restricted to acumen; apex acute to rounded or cuspidate, occasionally acuminate; alar cells quadrate to short-rectangular, 9–12 × 10–13 µm, walls moderately thick, region small, indistinctly delimited; laminal cells 45–60 × 4–7 µm; basal juxtacostal cells elongate, 10–20 × 5–7 µm. Seta: 0.9–1.6 cm, roughened throughout. Capsule: inclined. Spores: 15–19 µm.
Sub aqua tic habitats. low to high elevations (0-2000 m). B.C., Calif., Nev., Oreg., Wash.
Scleropodium occidentale is morphologically and ecologically similar to S. obtusifolium; however, it differs in having a longer, more robust costa that ends in a spine, and in DNA markers. It also often has acute leaf apices unlike the rounded apex typical of S. obtusifolium. The branches are tumid and often arching.