Description from Flora of China
Lycopodium pulvinatum Hooker & Greville, Hookers J. Bot. Kew Gard. Misc. 2: 381. 1831; Lycopodioides pulvinata (Hooker & Greville) H. S. Kung; Selaginella tamariscina (P. Beauvois) Spring var. pulvinata (Hooker & Greville) Alston.
Plants terrestrial or epilithic, xerophytic, "resurrectional"; stems forming rosette, seasonally green, stems and roots entangled forming treelike trunk, plants 2-10 cm, without creeping rhizomes. Rhizophores restricted to base of stem, 2-4 cm, rather thick or slender, much forked at end and forming thick massive rootstock. Main stems branched near and above base, pinnately branched, stramineous or brown, main stem ca. 1 mm in diam. at lower part; primary leafy branches 4-7 pairs, 2 or 3 times pinnately branched, branchlets dense, adjacent primary branches on main stem ca. 1 cm apart, leafy portion of main stem including leaves 2.2-2.4 mm wide at middle, ultimate branches 1.2-1.6 mm wide including leaves. Axillary leaves on main stems larger than those on branches; axillary leaves on branches symmetrical, ovate to triangular, ca. 2.5 × 1 mm, base exauriculate, margin lacerate-ciliolate. Dorsal leaves on branches imbricate, obliquely ovate or triangular, 2.8-3.1 × 0.9-1.2 mm, not carinate, base truncate (with a tuft of hairs), margin lacerate, outer margin revolute, apex aristate. Ventral leaves slightly ascending, asymmetrical, oblong, 2.9-3.2 × 1.4-1.5 mm, apex aristate, entire; basiscopic base not auriculate, margin lacerate, lower margin involute; acroscopic base enlarged, broader, overlapping stem and branches, margin lacerate. Strobili solitary, terminal, compact, tetragonal, 10-20 × 1.5-2 mm; sporophylls uniform, not white-margined, margin lacerate-ciliolate; megasporophylls in basal portion of strobili on lower side, in middle on lower side, or in upper portion on lower side; microspores pale yellow, megaspores white-yellow or dark brown.
Common in rock crevices on exposed rocky (limestone) ridges; (100-)1000-3000(-4300) m. Chongqing, S Gansu, Guangxi, Guizhou, Hebei, Henan, Liaoning, Shaanxi, Shanxi, Sichuan, Xizang [N India, Korea, Mongolia, Nepal, Russia (Siberia), Thailand, Vietnam].