Hastanectes is an extinct genus of a plesiosaurian with possible pliosaurid affinities known from the Early Cretaceous Wadhurst Clay Formation (Valanginian stage) of the United Kingdom. It contains a single species, Hastanectes valdensis, which was originally thought to be a species of Cimoliasaurus.
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