Williamia is a genus of small sea snails or false limpets, marine pulmonate gastropod molluscs in the family Siphonariidae, the false (air-breathing) limpets. Their development is similar to other Siphonariids
Species taxanomy provided by GBIF Secretariat (2022). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2023-06-13; License: CC BY 4.0