†order Thalattosauria Merriam 1905
Full reference: J. C. Merriam. 1905. The Thalattosauria. Memoirs of the California Academy of Sciences 5:1-53
Parent taxon: Thalattosauriformes according to E. L. Nicholls 1999
See also Carroll 1988, Cheng et al. 2007, Hay 1930, Kuhn 1946, Kuhn 1966, Merriam 1905, Nicholls and Brinkman 1993, Nopcsa 1923, Roxo 1937 and Sepkoski 2002
Sister taxa: none
Subtaxa: Askeptosauroidea Thalattosauroidea