| Name | Children | Media (from resource) | Traits |
|---|---|---|---|
| Acinetospora crinita | 0 | 0 | 1 |
| Acinetosporaceae | 7 | 0 | 0 |
| Acipenser | 1 | 0 | 0 |
| Acipenser sturio Linnaeus 1758 (Atlantic Sturgeon) | 0 | 0 | 1 |
| Acipenseridae (sturgeons) | 1 | 0 | 0 |
| Acipenseriformes (sturgeons and paddlefishes) | 1 | 0 | 0 |
| Aclididae | 1 | 0 | 0 |
| Aclis Lovén 1846 | 3 | 0 | 0 |
| Aclis gulsonae (W. Clark 1850) | 0 | 0 | 1 |
| Aclis minor (T. Brown 1827) | 0 | 0 | 1 |
| Aclis sarsi Dautzenberg & H. Fischer 1912 | 0 | 0 | 1 |
| Aclis walleri Jeffreys 1867 | 0 | 0 | 1 |
| Acmostomum | 1 | 0 | 0 |
| Acmostomum dioicum Metschnikoff 1865 | 0 | 0 | 1 |
| Acnanthales | 3 | 0 | 0 |
