Plants terrestrial or epilithic, evergreen, erect or creeping, 10-20 cm, fertile stems erect. Rhizophores restricted to lower part of erect fertile branches or at intervals throughout length of creeping stem and branches, borne on ventral side in axils of branches. Main stem pinnately branched, stramineous, 0.4-1.2 mm in diam. in lower part, terete, sulcate, erect fertile stems branched from lower part upward; primary leafy branches 3-5 pairs, once or twice pinnately branched, secondary branches once or twice forked, tertiary branches forked or simple, branchlets sparse and regular, adjacent primary branches on main stem 1.5-6 cm apart, leafy portion of main stem including leaves 3-6 mm wide at middle, ultimate branches 2.4-5.6 mm wide including leaves. Axillary leaves on main stems larger than those on branches, ovate, base not peltate, subcordate; axillary leaves on branches symmetrical, ovate or oblong, 1.4-2.6 × 0.4-1.2 mm, base exauriculate, margin denticulate. Dorsal leaves asymmetrical, those on branches not approximate, ovate or ovate-lanceolate, 1-1.6 × 0.4-0.8 mm, not carinate, base cuneate or obliquely attenuate, not peltate, margin minutely denticulate, apex acuminate or shortly aristate. Ventral leaves asymmetrical, those on main stem obviously larger than those on branches; ventral leaves on branches distant or approximate, spreading or deflexed, oblong-ovate, 1.8-2.7 × 0.7-1.8 mm, margin denticulate, apex acute; basiscopic base rounded; acroscopic base enlarged, broader, overlapping stem and branches. Strobili solitary, terminal, compact, dorsiventrally complanate, 5-25 × 1.5-3.5 mm; sporophylls strongly dimorphic, resupinate; dorsal sporophylls ovate-lanceolate or oblong-lanceolate, not keeled, margin ciliolate or denticulate, apex acuminate or aristate, with sporophyll-pteryx complete and ciliolate or denticulate; ventral sporophylls ovate-lanceolate, carinate (ridge also ciliolate), margin ciliolate, apex long acuminate; megasporophylls in basal portion on both sides or lower side of strobilus, ± randomly distributed on both sides, or throughout lower side, or megasporophylls and microsporophylls at intervals; microsporangia transversely elliptic, rather thin, cells uniform; microspores yellowish orange, megaspores yellowish orange.
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