| A (1 species) |
| Alierasaurus - Permian |
| B (0 species) |
| C (1 species) |
| Cotylorhynchus - Kungurian, 279.5-272 Ma |
| D (0 species) |
| E (3 species) |
| Ennatosaurus - 265-254 Ma |
| Eocasea - Late Carboniferous, 300 Ma |
| Eothyris - Early Permian,[1] Artinskian |
| F (0 species) |
| G (0 species) |
| H (0 species) |
| I (0 species) |
| J (0 species) |
| K (0 species) |
| L (0 species) |
| M (0 species) |
| N (0 species) |
| O (2 species) |
| Oedaleops - Early Permian |
| Oromycter - Early Permian 290.1-268 Ma |
| P (0 species) |
| Q (0 species) |
| R (0 species) |
| S (0 species) |
| T (0 species) |
| U (0 species) |
| V (0 species) |
| W (0 species) |
| X (0 species) |
| Y (0 species) |
| Z (0 species) |