Phylum [Vertebrata] (Lamarck, 1801) Class Reptilia Linnaeus, 1758 - reptiles Subclass †uncertain Order †Plesiosauria Blainville, 1835 - plesiosaurs Family †Cryptocleididae see Family Cryptoclididae Williston, 1925 Genus †Cryptocleidus Seeley, 1892 see Genus Cryptoclidus Seeley, 1892