| Species name | Common name | Distribution | Max. Length (cm) |
|---|---|---|---|
| Thecacera darwini Pruvot-Fol, 1950 |
Dalmatian sea slug | Southeast Pacific | |
| Thecacera pacifica (Bergh, 1883) |
Pacific thecacera | Indo-Pacific | 3.5 |
| Thecacera pennigera (Montagu, 1815) |
Rudman's thecacera | Circumglobal and the Mediterranean Sea | 2 |
| Thecacera picta Baba, 1972 |
Painted thecacera | Indo-West Pacific | 1 |