| 1 | Rhizome bearing hairs and scales; marginal cells of scales bearing papillose outgrowths |
| 1' | Rhizome bearing scales only; marginal cells of scales not bearing papillose outgrowths. |
| 2 | Fronds simple. |
| 2' | Fronds pinnately branched. |
| 3 | Sori elongate along the margin, protected by continuous indusia |
| 3' | Sori singly at ends of veins. |
| 4 | Indusium attached at base only (or slightly above base) |
| 4' | Indusium attached along sides as well as base |
| 5 | Fronds more or less copiously persistently hairy; lamina thin; indusium small, of various shapes. |
| 5' | Fronds not hairy when mature. |
| 6 | Indusium attached along base and whole of sides. |
| 6' | Indusium attached at base only, or also a little above the base, not along whole length of both sides. |
| 7 | Fronds trifoliate or simply pinnate with elongate narrow pinnae. |
| 7' | Fronds more copiously branched |
| 8 | Fronds much-branched, thin |
| 8' | Fronds of various form, lamina coriaceous or fleshy. |
| 9 | Scales with long acicular tips |
| 9' | Scales lacking long acicular tips |
