| Name | Children | Media (from resource) | Traits |
|---|---|---|---|
| Agrenia bidenticulata (Tullberg & T 1877) | 0 | 0 | 1 |
| Akanthophoreidae Sieg 1986 | 1 | 0 | 0 |
| Akanthophoreus Sieg 1986 | 1 | 0 | 0 |
| Akanthophoreus gracilis (Krøyer 1842) | 0 | 0 | 1 |
| Alabaminidae | 1 | 0 | 0 |
| Albanites | 1 | 0 | 0 |
| Albanites scalariforme | 0 | 0 | 1 |
| Albanitidae | 1 | 0 | 0 |
| Alcedinidae | 2 | 0 | 0 |
| Alcedo Linnaeus 1758 | 1 | 0 | 0 |
| Alcedo atthis (Linnaeus 1758) | 0 | 0 | 1 |
| Alcidae | 4 | 0 | 0 |
| Alcyonacea Lamouroux 1812 | 1 | 0 | 0 |
| Alcyonidiidae Johnston 1837 | 1 | 0 | 0 |
| Alcyonidium J. V. F. Lamouroux 1813 | 3 | 0 | 0 |
