16. Selaginella limbata Alston, J. Bot. 70: 62. 1932.
具边卷柏 ju bian juan bai
Plants terrestrial, seasonally green, long creeping, branches ascending, 50-100 cm or more. Rhizophores at intervals throughout length of main stem, borne on ventral side in axils of branches. Main stems branched throughout, stramineous, 0.4-1.4 mm in diam. in lower part, subquadrangular or angulate, sulcate, branches many, some primary lateral branches developing into long branch systems; primary leafy branches 2-5 pairs, 2 or 3 times forked, branchlets sparse, adjacent primary branches on creeping main stems 4-10 cm apart, leafy branches dorsiventrally flattened, ultimate branches 2.4-5.6 mm wide including leaves. All leaves entire and white-margined. Axillary leaves on main stems obviously larger than those on branches, suborbicular, base subcordate; axillary leaves on branches symmetrical, elliptic or broadly elliptic, 1.3-2.8 × 0.8-1.8 mm. Dorsal leaves asymmetrical; dorsal leaves on branches imbricate, overlapping at leaf apex, ovate-elliptic, 0.8-1.6 × 0.3-1 mm, not carinate, base uniauriculate at basiscopic side, apex long acuminate. Ventral leaves asymmetrical, those on main stem larger than those on branches; ventral leaves on branches approximate or contiguous, spreading, ovate-lanceolate or oblong, 1.5-3 × 0.8-1.6 mm, apex acute; basiscopic base slightly dilated; acroscopic base rounded, not overlapping stem and branches. Strobili solitary, terminal, compact, tetragonal, 5-12 × 1.8-3.3 mm; sporophylls uniform, white-margined, ovate, carinate, margin entire, apex acuminate; megasporophylls and microsporophylls at intervals or only 1 megasporophyll at base on lower side of strobilus, elsewhere microsporophylls or megasporophylls in middle on lower side; microsporangia cordate or transversely elliptic, relatively thick, marginal cells differentiated, longer; microspores pale yellow, megaspores dark brown, baculate.
Under shrubs on sunny slopes, forests, common in coastal regions of E China; below 100-1000 m. Fujian, Guangdong, Hunan, Jiangxi, Zhejiang [Japan (Amami Oshima)].
Plants of Selaginella limbata found in shade are usually sterile.