| Name | Children | Media (from resource) | Traits |
|---|---|---|---|
| Acaena (acaena) | 2 | 0 | 0 |
| Acaena magellanica (Lam.) Vahl (buzzy burr) | 0 | 0 | 2 |
| Acaena magellanica (Lam.) Vahl (buzzy burr) | 0 | 0 | 2 |
| Acarnidae Dendy 1922 | 1 | 0 | 0 |
| Actinopterygii (ray-finned fishes) | 2 | 0 | 0 |
| Adenophorea | 1 | 0 | 0 |
| Adoncholaimus Filipjev 1918 | 1 | 0 | 0 |
| Adoncholaimus crassicaudatus | 0 | 0 | 1 |
| Aglaophamus Kinberg 1866 | 1 | 0 | 0 |
| Aglaophamus macroura (Schmarda 1861) | 0 | 0 | 1 |
| Agyriaceae | 0 | 0 | 0 |
| Agyriales | 1 | 0 | 0 |
| Amalopteryx | 1 | 0 | 0 |
| Amalopteryx maritima Eaton 1875 | 0 | 0 | 1 |
| Amandinea | 1 | 0 | 0 |
