Colymbosaurus is a genus of cryptoclidid plesiosaur from the Late Jurassic (Kimmeridgian-Tithonian) of the UK and Svalbard, Norway. There are two currently recognized species, C. megadeirus and C. svalbardensis.
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