| Synonym | Author | CoL Status | Valid | Synonymy | Combination |
|---|---|---|---|---|---|
| Sipunculus balanophorus | delle Chaiaje, 1823 | synonym | No | junior synonym |
original combination |
| Sipunculus delphinus | Murina, 1967 | synonym | No | junior synonym |
original combination |
| Sipunculus eximioclatharus | Baird, 1868 | synonym | No | junior synonym |
original combination |
| Sipunculus gigas | de Quatrefages, 1865 | synonym | No | junior synonym |
original combination |
| Sipunculus nudus | Linnaeus, 1766 | accepted name | Yes | senior synonym |
original combination |
| Sipunculus nudus tesselatus | (Rafinesque, 1814) | synonym | No | junior synonym |
change in rank |
| Sipunculus nudus var. tessalatus | (Rafinesque, 1814) | synonym | No | junior synonym |
new combination |
| Sipunculus tesselatus | (Rafinesque, 1814) | synonym | No | junior synonym |
new combination |
| Sipunculus titubans | Selenka & Bülow, 1883 | synonym | No | junior synonym |
original combination |
| Sipunculus titubans var. diptychus | (Selenka & Bülow, 1883) | synonym | No | junior synonym |
change in rank |
| Syrinx nudus | Forbes, 1841 | synonym | No | senior synonym |
original combination |
| Syrinx tesselatus | Rafinesque, 1814 | synonym | No | junior synonym |
original combination |