Prestosuchidae

Prestosuchidae Temporal range: Middle - Late Triassic, 245–216 Ma PreЄ Є O S D C P T J K Pg N
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Mounted skeleton of Prestosuchus at the American Museum of Natural History.
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Loricata
Family:	†Prestosuchidae Romer, 1966
Genera
See text.

Prestosuchids were a group of Triassic carnivorous archosaurs. They were large active terrestrial apex predators, ranging from around 2.5 to 7 metres (8.2 to 23.0 ft) in length. They succeeded the Erythrosuchidae as the largest archosaurs of their time. While resembling erythrosuchids in size and some features of the skull and skeleton, they were more advanced in their erect posture and crocodile-like ankle, indicating more efficient gait. Prestosuchids flourished throughout the whole of the middle, and the early part of the late Triassic, and fossils are so far known from Europe, India, Africa (Tanganyika), Argentina,and Paleorrota in Brazil. However, experts disagree regarding the phylogenetic relationships of the group, what genera should be included, and whether indeed the Prestosuchidae constitute a distinct family apart from the Rauisuchidae.

Classification

In 1957, Alan Charig proposed a new family, the Prestosuchidae, to include genera like Mandasuchus, Prestosuchus, and Spondylosoma.

In 1967, Alfred Sherwood Romer placed Saurosuchus and Rauisuchus within Erythrosuchidae and adopted the Prestosuchidae to include Prestosuchus, Procerosuchus, and Charig's "Mandasuchus".

Prestosuchidae have often been included within Rauisuchidae, although they have sometimes considered the sister group of the aetosaurs in a monophyletic Pseudosuchia, or as a small clade intermediate between basal Crurotarsi and more advanced archosaurs such as the Aetosauridae and Rauisuchidae. J. Michael Parrish's 1993 cladistic analysis of crocodylotarsan archosaurs places the Prestosuchidae (including Prestosuchus, Ticinosuchus, and Saurosuchus) outside the crocodylomorph - poposaurid - rauisuchid - aetosaur clade. In most cladograms Prestosuchids are considered more derived than phytosaurs and ornithosuchids, but usually less derived than the poposaurids and aetosaurs.

Evolution of the group

The earliest known prestosuchid is Mandasuchus from the Anisian of Tanganyika. This was already a large animal, about 4.75 meters long. A similar but smaller form (perhaps the same genus) is Ticinosuchus of the Middle Triassic (Anisian-Ladinian) of Switzerland and Northern Italy, which was about 2.5 meters in length. The huge (6 meters long) Batrachotomus from the latest Middle Triassic (Late Ladinian) of Germany, and Prestosuchus of the early Late Triassic (Carnian) of Brazil may have been closely related animals. Yarasuchus was a lightly built animal from the Middle Triassic of India that also seems to belong to this group. Finally, Saurosuchus was a huge carnivore, 6 or 7 meters long, whose fossils are known from the Late Carnian of Argentina.

List of genera

Genus	Authors	Year	Status	Age	Location	Unit	Description	Images
Batrachotomus	Gower	1999	Valid	Late Ladinian	Germany	Kupferzell, Crailsheim and Vellberg-Eschenau
Decuriasuchus	França Ferigolo Langer	2011	Valid	Ladinian	Brazil	Santa Maria Formation		200px
Karamuru	Kischlat	2000	Junior synonym	Middle Triassic	Brazil	Santa Maria Formation	Probable synonym of Prestosuchus
"Mandasuchus"	Charig	1957	Nomen nudum	Middle Triassic	Tanzania	Manda Formation	Nomen nudum, probable synonym of Ticinosuchus
Prestosuchus	Huene	1942	Valid	Late Triassic	Brazil	Santa Maria Formation
Saurosuchus	Reig	1959	Valid	Late Carnian	Argentina	Ischigualasto Formation
Ticinosuchus	Krebs	1965	Valid	Late Anisian	SwitzerlandItaly	Mittlere Grenzbitumenzone		200px

References

• Sereno, P. C. 2005. Stem Archosauria—TaxonSearch [version 1.0, 7 November 2005]

External links

• Taxon Search - Prestosuchidae
• Rauisuchiformes: Prestosuchidae at Palaeos