Cryptoclidus Seeley, 1892
Cryptoclidus, often mis-spelled 'Cryptocleidus' after Andrews (1909), but correctly spelled "...clidus", is a moderately sized (up to 3 meters long) plesiosaur known from a large number of individuals from the Oxford Clay. The fossils of Cryptoclidus are especially common and so a complete ontogenetic sequence from very young to old adult individuals is known. This makes Cryptoclidus one of the most studied and best understood plesiosaurs. Full skeletal restoration of Cryptoclidus can be seen in most major museums including the Musee Palaeontologique in Paris, France; the Natural History Museum, London, England; the Hunterian Museum, Scotland, and the American Museum of Natural History, New York, USA.
The genus has diagnostic teeth with reduced ornamentation. There are six teeth in each premaxilla. Cryptoclidus lacks suborbital fenestrae on the palate and the palate has large anterior interpterygoid vacuities. A small foramen is located along the postorbital-squamosal junction in C. eurymerus. Cryptoclidus used its numerous sharp teeth to catch squid and fish or perhaps to sift the silty sediment for benthic animals such as crustaceans.
C. richardsoni differs from C. eurymerus only in the form of the humerus which is more greatly expanded. The genus and species 'Apractocleidus teretipes' was introduced by Smellie (1916) for what is now considered to be an old-adult specimen of Cryptoclidus.
Classification
Sauropterygia --> Eosauropterygia --> Eusauropterygia --> Pistosauroidea --> Plesiosauria --> Plesiosauroidea --> Cryptoclididae
C. eurymerus Phillips, 1871
Material
Type specimen: BMNH 22656, complete skeleton.
Referred material: lots
Age and Location
Lower Oxford Clay, Late Jurassic and Lower Cretaceous of Peterborough, Cambridgeshire and Bedfordshire, (England).
C. richardsoni Lydekker, 1889
Material
Type specimen: ?
Referred material: ?
Age and Location
Lower Oxford Clay, Late Jurassic of Dorset, (England).
Cryptoclidus images
Adult individual of Cryptoclidus in the Natural History Museum, London.
Cryptoclidus excavation.
Cryptoclidus excavtion.
Cryptoclidus in the Hunterian Museum, Glasgow, Scotland. Photo by Adam S. Smith. 2007.
Young individual of Cryptoclidus in the Natural History Museum, London. Photo by Adam S. Smith 2005.
Young individual of Cryptoclidus in the Natural History Museum, London.
Young individual of Cryptoclidus in the Natural History Museum, London.
Adult Cryptoclidus, American Museum of Natural History, New York. Photo by Adam S. Smith
Adult Cryptoclidus, American Museum of Natural History, New York. Photo by Adam S. Smith
Adult Cryptoclidus, American Museum of Natural History, New York.
Cryptoclidus 'oxoniensis' = eurymerus. Postcard from the Paris Musee de Paleontologie.
Cryptoclidus in Tubingen.
Cryptoclidus in Tubingen.
