Hymenophytaceae

Epiphytic, lithophytic and terrestrial, dioicous with male and female plants similar size. Specialised asexual propagules absent. Plants comprising a prostrate or subterranean branching stem, an unbranched basal stipe that diverges away from the substrate and a terminal repetitively forked frond section; stipe with a narrow wing of one cell thick thallus on both sides that gradually broadens towards the frond base; frond cuneate, flabellate to almost circular in outline, held horizontally, often bent at an angle to stipe, with 3–6 forks, each branch comprising a central midrib and membranous one cell thick thallus, olive or lime to emerald (not in Victoria) green; thallus margins entire, sometimes slightly undulate; thallus cells polygonal, thin-walled, without trigones, with spherical oil bodies. Abaxial appendages stalked papillae in 2 rows. Rhizoids along prostrate or subterranean stem, smooth, hyaline. Antheridia on short abaxial branches arising from the stipe, or from the frond near the stipe and frond junction or midrib bifurcation, enclosed by a small pale scale. Sporophytes surrounded by calyptra, caulocalyx, and involucre on a short abaxial protuberances; involucre an adaxial scale with entre to toothed and occasionally ciliate margins accompanied abaxially by a larger scale-like wing of the short abaxial branch and together forming a bilabiate structure; calyptra short, fleshy; caulocalyx long, cylindric, toothed at apex; pseudoperianth absent. Seta elongate, elevating capsule well above frond. Capsule cylindric, bistratose, dehiscing into 4 valves; elaters present, bispiral. Spores globose, smooth, greenish, shed singly.