Plants terrestrial, evergreen or seasonally green, erect, 45-80(-110) cm, with creeping subterranean rhizome and stolons. Rhizophores restricted to base of stem. Main stems branched at or above lower part or at or above middle, pinnately branched, obviously zigzag, stramineous, unbranched main stem (5-)10-20 cm tall, 2-4 mm in diam. at lower part, angulate, sulcate, glabrous or pubescent on leafy branched portion; primary leafy branches 5-7 pairs, 2 or 3 times pinnately branched, secondary branches once or twice pinnately branched, branchlets dense and regular, adjacent primary branches on main stem 6-12 cm apart, leafy branches pubescent on both sides, dorsiventrally flattened, leafy portion of main stem including leaves 6-8 mm wide at middle, ultimate branches 3-5 mm wide including leaves. Axillary leaves on branches symmetrical, narrowly elliptic, 2.4-4.2 × 2-3.4 mm, base biauriculate, margin entire. Dorsal leaves on branches asymmetrical, overlapping at leaf apex, falcate, 1.2-1.5 × 0.4-0.6 mm, base cuneate, margin entire, apex acute. Ventral leaves on branches approximate to contiguous, slightly ascending or spreading, asymmetrical, oblong or falcate, 2.5-4 × 0.8-1.4 mm, margin entire, apex acuminate; basiscopic base not auriculate; acroscopic base with triangular auricle, not overlapping stem and branches. Strobili solitary, terminal, compact, tetragonal, 4-10 × 1.4-3.5 mm; sporophylls uniform, white-margined, broadly ovate or suborbicular, slightly carinate, margin entire, apex acute or acuminate; megasporophylls only 1 in middle on lower side of strobilus, or at base on lower side, elsewhere with microsporophylls; microsporangia suborbicular, rather thin, marginal cells differentiated, smaller with thin walls, microspores pale yellow, megaspores dark brown.
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