48. Selaginella pennata (D. Don) Spring, Bull. Acad. Roy. Sci. Bruxelles. 10: 232. 1843.
拟双沟卷柏 ni shuang gou juan bai
Lycopodium pennatum D. Don, Prodr. Fl. Nepal. 18. 1825; Selaginella blepharostachya Alston ex Knox; S. suberosa Spring.
Plants terrestrial, seasonally green, suberect or ascending from decumbent base, 15-30 cm. Rhizophores restricted to lower part of stem. Main stems branched from lower part upward, not very regularly pinnately branched, stramineous, shiny, 0.8-2.7 mm in diam. in lower part, terete, not sulcate or sulcate in upper part, branches few; primary leafy branches 3-5 pairs, twice pinnately branched, secondary branches forked or once pinnately branched, branchlets regularly long, adjacent primary branches on main stem 3-6 cm apart, leafy portion of main stem including leaves 5-7 mm wide at middle, ultimate branches 3.5-5.7 mm wide including leaves. Axillary leaves on branches symmetrical, ovate, 1.5-2.3 × 0.6-1.2 mm, base exauriculate, margin ciliolate in basal part, upward subentire, or with 1 or 2 cilia. Dorsal leaves approximate, asymmetrical, 1.2-2.1 × 0.4-0.8 mm, base obliquely cuneate, margin sparsely ciliolate, apex mucronate or aristate with arista curved, up to 1/2-3/4 as long as leaf, 0.5-0.8 mm. Ventral leaves asymmetrical, those on main stem larger than those on branches; ventral leaves on branches distant, slightly ascending, oblong or oblong-ovate, 1.6-3 × 0.7-1.4 mm, apex acute or apiculate; basiscopic margin entire; acroscopic base rounded, not overlapping stem and branches, margin sparsely shortly ciliolate. Strobili solitary or in pairs, terminal, compact, dorsiventrally complanate, 6-12 × 2.5-4.5 mm; sporophylls unlike sterile leaves, strongly dimorphic, very basal sporophylls on ventral side of strobilus similar to lateral sterile leaves; dorsal sporophylls oblong-lanceolate, with incomplete sporophyll-pteryx; ventral sporophylls ovate or broadly ovate, not carinate, base dilated, margin lacerate-ciliolate; megasporophylls in basal portion on lower side; microsporangia reniform, relatively thick, marginal cells differentiated, longer; microspores pale yellow, megaspores whitish, gray, or dark brown, baculate.
Mixed forests on rather dry mountain slopes; 400-1200 m. Yunnan [NE India, Myanmar, Nepal, Thailand].
Selaginella pennata is very close to S. bisulcata in the shape of the dorsal leaves and the color and ornamentation of the megaspores.