| 1 | Pinnae commonly (9-)15 pairs or more, the sterile pinnae to at least 15 by 3 cm; fertile pinnae with very narrow sterile margin |
| 1' | Pinnae to 7 pairs; sterile pinnae to 10 by 2.2 cm; fertile pinnae 3 mm wide with thin reflexed sterile margins 1 mm wide |
| 2 | Lower pinnae at least appearing fully articulate when dry; pinna-bases cuneate; fertile pinnae 2-3 mm wide; spores evenly tuberculate throughout |
| 2' | Pinnae not distinctly articulate; sterile pinnae with broadly rounded to cordate bases; fertile to at least 5 mm wide; spores with raised ± broken ridges |
| 3 | Sterile pinnae broadly rounded at base, sometimes partly articulate; fertile pinnae (3-)5-8 mm wide; spores with irregular broken ridges |
| 3' | Sterile pinnae cordate at base, not at all articulate; fertile pinnae 7-10 mm wide; spores with parallel continuous or broken ridges |
