1	"Stipe and basal frond leaves in 8 ranks; dorsal leaves present in basal part of rachis; laminal cells parenchymatous to prosenchymatous, rectangular or hexagonal; terminal cell of axillary hairs usually short-linear to linear, smooth or covered with white substances (cells with white substances visible as white dots with hand lens)"	"Hypopterygium didictyon"
1	"Stipe and basal frond leaves in 3 or 11 (or more) ranks; dorsal leaves absent; laminal cells prosenchymatous, hexagonal; terminal cell of axillary hairs short to elongate, never short-linear or linear, smooth or weakly covered with white substances (only visible with light microscope)"	2
2	"Dioicous; plants usually strongly palmate to umbellate, rarely flabellate, not gemmiferous; stipe frequently more than 15 mm long; distal frond leaves weakly to coarsely serrate-dentate, not caducous; teeth usually more than 20; border green"	"Hypopterygium discolor"
2	"Monoicous or dioicous; plants pinnate to bipinnate (or partly tripinnate), palmate or umbellate, gemmiferous or not; stipe less than 15 mm long; distal frond leaves entire or weakly serrate to weakly serrate-dentate, occasionally caducous in palmate to umbellate plants; teeth fewer than 20; border colourless"	"Hypopterygium tamarisci"