| Name | Children | Media (from resource) | Traits |
|---|---|---|---|
| Acipenseridae (sturgeons) | 4 | 2 | 0 |
| Acipenseriformes (sturgeons and paddlefishes) | 1 | 2 | 0 |
| Acipenserinae | 0 | 2 | 0 |
| Aciphylla (fierce Spaniard) | 1 | 2 | 0 |
| Aciphylla colensoi Hook. fil. | 0 | 2 | 0 |
| Aciphylleae | 2 | 2 | 0 |
| Aclididae | 1 | 0 | 0 |
| Aclis Lovén 1846 | 1 | 0 | 0 |
| Aclis ascaris (W. Turton 1819) | 0 | 2 | 0 |
| Acoelomorpha | 0 | 2 | 0 |
| Aconchulinida | 1 | 0 | 0 |
| Aconoidasida | 1 | 2 | 0 |
| Acrantophis Jan ex Jan & Sordelli 1860 (boa) | 1 | 0 | 0 |
| Acrantophis dumerili Jan ex Jan & Sordelli 1860 (Dumeril's Boa) | 0 | 2 | 0 |
| Acrasida | 1 | 0 | 0 |
