Plants terrestrial, seasonally green, erect, generally less than 10 cm, stramineous, glabrous. Rhizophores restricted to base of stem. Main stem pinnately branched, stramineous, branched from lower part, 0.4-0.7 mm in diam. in basal part, leaves on lower part of main stems or below leafy portion distant, with single vascular bundle; primary leafy branches 3-5 pairs, forked, branchlets sparse, middle primary branches ca. 3 cm, ca. 2 cm wide, leafy branches glabrous, dorsiventrally flattened, ultimate branches 1.5-2.5 mm wide including leaves. Leaves decussately arranged except on unbranched main stem, dimorphic throughout, herbaceous, white-margined, entire. Dorsal leaves asymmetrical; dorsal leaves on branches elliptic, ca. 1.2 × 0.4 mm, base cuneate, margin denticulate, apex long acuminate. Ventral leaves asymmetrical; ventral leaves on branches ascending, approximate, oblong, ca. 2 × 1.5 mm, apex acute; acroscopic base rounded, decurrent, margin denticulate. Strobili solitary, terminal, compact, dorsiventrally complanate, ca. 5 × 2.5 mm; sporophylls strongly dimorphic, resupinate; dorsal sporophylls ovate, margin denticulate, apex acute, with sporophyll-pteryx incomplete, ciliate; ventral sporophylls ovate, margin denticulate or ciliate; megasporangia usually in basal portion on lower side or megasporangia in basal portion of both sides; microspores orange-red, megaspores yellow.
Yunnan [India (Assam), Malaysia, Myanmar, Thailand, Vietnam].
On soil banks in shaded forests; 100-1300 m.