Selaginella densa is a species of spikemoss known by the common names lesser spikemoss, prairie spikemoss, and Rocky Mountains spikemoss. It is native to western North America, where it can be found from Alaska to Ontario, the Dakotas, Texas and far northern California. This lycophyte forms mats or cushions of creeping stems which fork into small, upright branches. The green, linear or lance-shaped leaves are up to 5 millimeters long including the short, soft bristles on the tips. They are flattened to the stem. The strobili at the ends of the stems can be up to 3 or 4 centimeters long.