| 1 | Inner indusium smaller than outer; midribs of quaternary leaflets rather closely hairy on lower surface. Mountain plants. |
| 1' | Inner indusium at maturity larger than outer, pouch-shaped and not reflexed; midribs of quaternary leaflets sparsely hairy. Lowland plants |
| 2 | Largest quinary lobes commonly with only one sorus |
| 2' | Largest quinary lobes commonly with 3 or 2 sori |
