Williamia gussoni
- kingdom: Animalia
- phylum: Mollusca
- class: Gastropoda
- order:
- family: Siphonariidae
- genus: Williamia
- species: Williamia gussoni
Aci Trezza
Acitrezza
Sicily
ItalyFajã de Baixo
Rosto de Cão
Azores
PortugalCeuta
Ceuta
Spain