| Naetrocymbe | Naetrocymbe laburni |
| Naetrocymbe nitescens | |
| Naetrocymbe punctiformis | |
| Naetrocymbe saxicola | |
| Nephroma | Nephroma arcticum |
| Nephroma helveticum | |
| Nephroma laevigatum | |
| Normandina | Normandina acroglypta - GBI populations on bark are probably N. chlorococca |
| Normandina chlorococca | |
| Normandina pulchella | |
| Normandina sp. P5000 |