Welcome to the Plesiosaur Directory, your online resource for everything 'plesiosaur'. During the Mesozoic Era between 245 to 65 million years ago, when dinosaurs dominated the land, the waters of the world were inhabited by an equally spectacular variety of reptiles. Amongst the first fossil vertebrates to be discovered and recognised by scientists, these 'sea-dragons' occurred in all sorts of shapes and sizes. But perhaps the most unusual of these extinct groups of fascinating prehistoric marine reptiles were the sauropterygians: plesiosaurs and their kin.

Sauropterygians are a group of carnivorous diapsid reptiles. The most popular and widely recognised of these are the long-necked plesiosauroids, they possess four large flippers, short tails and barrel shaped bodies. The closely related pliosauroids (often called just 'pliosaurs') had shorter necks and large heads. However, sauropterygians were very diverse and there are many other interesting forms such as the placodonts, pachypleurosaurs, nothosaurs, and an array of intermediates.

This website is designed as a resource for anyone interested in any aspect of the plesiosaurs and their kin - this is a long-term aim and the site will always be under development as ourunderstanding of plesiosaurs develop. You will find scientific information regarding the anatomy, classification and evolution of the group, information on specific genera and species, and data on their palaeobiology - how the animals were in life, how they swam and ate. Stay up to date with the latest discoveries on the News page and archives. I also include pages about the people behind the science (in development), and about plesiosaurs in popular culture: films, toys and monsters. I have endeavoured to make this site as image-rich as possible, using photographs of fossils, reconstructions of fossils, and restorations of the possible appearance of the animals in life. Plus, You can get your fill of plesiosaur books and toys in the Plesio-Store! Still yearning for more? Subscribe to the mailing list of the The Plesiosaur Directory Newsletter and don't forget to join in the ongoing discussions at the Plesiosaur Forum.