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Prestosuchidae (in its widest usage) is a polyphyletic grouping of carnivorous that lived during the Triassic. They were large active terrestrial , ranging from around 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 (Tanzania), Argentina, and Paleorrota in Brazil. However, for a long time experts disagree regarding the phylogenetic relationships of the group, what genera should be included, and whether indeed the "Prestosuchidae" constitute a distinct family.
In 2011, Prestosuchidae in its broadest definition was determined to be a poorly-diagnosed and obsolete Polyphyly group of (-lineage archosaurs) leading to the more "advanced" Rauisuchidae and Crocodylomorpha. Some studies since then have reintroduced the term Prestosuchidae in a more limited setting. In these studies it refers to a clade containing Prestosuchus, Saurosuchus, and Luperosuchus. Even so, the validity of this clade is unclear, and it is often not supported over a Paraphyly arrangement of its constituents.
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 Synapomorphy than and ornithosuchidae, but usually less derived than the poposauridae and .
A 2011 study of archosaurs by Sterling Nesbitt found that Prestosuchidae is a polyphyletic group of various unrelated . For example, Ticinosuchus was found to be the sister taxon to Paracrocodylomorpha while Prestosuchus and Saurosuchus were basal . The study determined that many of the characteristics previously used to define Prestosuchidae were present in a wide variety of . Although Parrish used many traits of the ankle to characterize prestosuchids, Nesbitt showed that these traits were present in various basal suchian groups. In 2004, Benton proposed another trait to define Prestosuchidae: a narrow, triangular antorbital fenestra. However, Nesbitt found this trait in Postosuchus (a Rauisuchidae), Dromicosuchus (a Crocodylomorpha), and Fasolasuchus (a basal loricatan).
Evolution of the group
The earliest known "prestosuchid" is Mandasuchus from the Anisian of Tanzania. 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, a lightly built archosaur from the Middle Triassic of India, was once assigned to this group, although a 2017 study placed it as an in the newly defined group Aphanosauria. Finally, Saurosuchus was a huge carnivore, 6 or 7 meters long, whose fossils are known from the Late Carnian of Argentina.
List of genera
Batrachotomus Gower
1999 Valid Late Ladinian Kupferzell, Crailsheim and Vellberg-Eschenau Decuriasuchus França
Ferigolo
Langer
2011 Valid Ladinian Santa Maria Formation Heptasuchus? Robert M. Dawley, John M. Zawiskie and J. W. Cosgriff 1979 Valid Carnian Popo Agie Formation Karamuru Kischlat
2000 Junior synonym? Middle Triassic Santa Maria Formation Dubious, probably a synonym of Prestosuchus Luperosuchus Romer
1971 Valid Late Ladinian or Early Carnian Chanares Formation Mandasuchus Butler et al.
2018 Valid Anisian Manda Formation Prestosuchus Huene
1942 Valid Late Triassic Santa Maria Formation Saurosuchus Reig
1959 Valid Late Carnian Ischigualasto Formation Stagonosuchus Huene
1938 Junior synonym? Anisian Manda Formation May be a junior synonym of Prestosuchus, or outside Loricata (possibly a Poposauroidea) Ticinosuchus Krebs
1965 Valid Late Anisian Mittlere Grenzbitumenzone
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