Stems decumbent (plants low, mounded, mostly to 5 dm); internodes 1.5–4.5 mm; young stems glabrous. Leaves clavate, semiterete, 2–6.3 mm, apex acute.

Flowering (Apr–)May–Jun(–Aug). Maritime chaparral; 0–200(–500) m; Calif.

Variety prostratum is known from the Channel Islands (San Nicolas, Santa Catalina, Santa Cruz, Santa Rosa islands) and the adjacent mainland (San Luis Obispo County) in southern California, where it often co-occurs with var. fasciculatum. The plants maintain their low-mounded habit in cultivation.