Thalattosuchia

Unikonta

Thalattosuchia Temporal range: 195–136 Ma PreЄ Є O S D C P T J K Pg N Sinemurian - Valanginian
Dakosaurus, a metriorhynchid.
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Superorder:	Crocodylomorpha
clade:	Mesoeucrocodylia
Suborder:	†Thalattosuchia Fraas, 1901[1]
Families
†Metriorhynchidae[2] †Teleosauridae

Thalattosuchia is the name given to a clade of marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution. They are sometimes colloquially referred to as marine crocodiles or sea crocodiles, though they are not actually members of Crocodilia.

The term Thalattosuchia was coined by Fraas in 1901.^[1] Various authors have considered Thalattosuchia to be either an infraorder or a suborder within "Mesosuchia". However, the term "Mesosuchia" is a paraphyletic group, and as such is no longer used. For consistency, the Thalattosuchia are here placed at suborder rank although the order that contains it is presently unnamed.

Pelagosaurus, a teleosaurid.

Since Buffetaut (1982)^[3] demonstrated the shared characteristics of the early forms of Metriorhynchidae and Teleosauridae, Thalattosuchia has consisted of these two families. Some of the early members of Teleosauridae have been discovered in non-marine deposits suggesting thalattosuchians 'moved' from being semi-aquatic freshwater forms to fully marine forms.^[3] The systematics of the genus Pelagosaurus are confused, with differencing topologies placing it as either a teleosaurid ^[4], or as the sister taxon to a Teleosauridae + Metriorhynchidae clade. Other authors have considered Pelagosaurus to be a basal metriorhynchid.^[3]

References

1. ^ ^{a b} Fraas E. 1901. Die Meerkrokodile (Thalattosuchia n. g.) eine neue Sauriergruppe der Juraformation. Jahreshefte des Vereins für vaterländische Naturkunde, Württemberg 57: 409-418.
2. ^ Fitzinger LJFJ. 1843. Systema Reptilium. Wien: Braumüller et Seidel, 106 pp.
3. ^ ^{a b c} Buffetaut, E. 1982. Radiation évolutive, paléoécologie et biogéographie des Crocodiliens mésosuchienes. Mémoires Societé Geologique de France 142: 1–88.
4. ^ Gasparini Z, Pol D, Spalletti LA. 2006. An unusual marine crocodyliform from the Jurassic-Cretaceous boundary of Patagonia. Science 311: 70-73.

Suggested further reading

• Fraas, E. (1902). Die Meer-Krocodilier (Thalattosuchia) des oberen Jura unter specieller Berücksichtigung von Dacosaurus und Geosaurus. Paleontographica 49: 1-72.

See also

• List of marine reptiles