| Name | Children | Media (from resource) | Traits |
|---|---|---|---|
| Acanthocorbis S. Hara & E. Takahashi 1984 | 1 | 0 | 0 |
| Acanthocorbis unguiculata | 0 | 0 | 1 |
| Acanthoecaceae | 1 | 0 | 0 |
| Acanthoecidae | 4 | 0 | 0 |
| Acarospora (cracked lichen) | 1 | 0 | 0 |
| Acarospora fuscata | 0 | 0 | 1 |
| Acarosporaceae | 1 | 0 | 0 |
| Acarosporales | 1 | 0 | 0 |
| Accipitridae (hawks, eagles, and relatives) | 1 | 0 | 0 |
| Accipitriformes | 1 | 0 | 0 |
| Aconchulinida | 1 | 0 | 0 |
| Actinomonas Kent 1880 | 1 | 0 | 0 |
| Actinomonas mirabilis | 0 | 0 | 1 |
| Actinopterygii (ray-finned fishes) | 7 | 0 | 0 |
| Adenophorea | 1 | 0 | 0 |
