| 1 | Lamina narrowly triangular to narrowly ovate in outline, fertile and sterile fronds dimorphic; next to basal pair of pinnae as long as or longer than middle pinnae; lowest pairs of pinnae auriculate; stipe and rhachis lacking hairs |
| 1' | Lamina elliptic, narrowly elliptic or narrowly obovate; fertile and sterile fronds not or slightly dimorphic; lower pinnae as long as or shorter than middle pinnae, not auriculate; stipe and rhachis with or without hairs |
| 2 | Stipe and rhachis with hairs; costa of pinna without scales |
| 2' | Stipe and rhachis without hairs; costa of pinna with scales |
