Hymenophyllaceae

Fronds delicate, translucent, usually 1 cell thick, lacking stomates. Receptacle elongated and columnar. Epiphytic or rupestral ferns under 12 cm high Hymenophyllaceae
Involucre bivalvate (deeply or to the base) or bivalvate in the upper portion but obconic at the base Hymenophyllum
Margin of the lamina and the axes not clothed with branched hairs
Margin of the lamina entire
Lamina pinnately divided. Involucre and lamina without a black thickened margin
Main rhachis winged; the wing usually continuous down the stipe
Sori free, terminal on the ultimate segments, often in pairs. Stipes broadly winged with a crisped or flat wing. Fronds 1–3-pinnate-pinnatifid, 5–25 cm long including the stipes, 10–55 mm broad. Widespread, common in Blue Mts. RF or tall open forests on rocks tree ferns or trees Hymenophyllum australe
Sori immersed in the apices of the ultimate segments. Stipes with a short flat wing or unwinged. Fronds 1-pinnate-pinnatifid, 1.2–14 cm long including the stipes, 8–20 mm broad. Widespread. Uncommon. RF on tree ferns, rocks or trees H. rarum rarumH. rarum