Named By: L. I. Price - 1948.
Classification: Chordata, Amphibia, Temnospondyli, Archegosauridae, Platyoposaurinae.
Species: P. plummeri (type).
Size: Most specimens estimated to be about 2-2.5 meters long. One excpetionally large skull however has a length of about 1.6 meters, suggesting that this individual had a total body length of about 9 meters.
Known locations: Brazil - Pedra do Fogo Formation.
Time period: Mid Permian.
Fossil representation: Several individuals, usually of skulls.
was a temnospondyl amphibian that lived in South America during the
Permian, and one that was surprisingly crocodile-like in appearance
with a snout similar to that of a gharial crocodile. Most specimens
of Prionosuchus are fairly small at only about two
and a half meters in
length, but one exceptionally large skull just over one and a half
meters in length has yielded a truly terrifying proposition. With a
skull this large the total body length achievable for Prionosuchus
would have been up to nine meters long, something that not only makes
Prionosuchus possibly the largest temnospondyl
amphibian known, but
also one of the biggest predators of the Permian.
Most temnospondyl amphibians are perceived to be hunters of aquatic organisms such as fish and other amphibians, and there certainly is no evidence to refute this for Prionosuchus. With the additional possibility of individuals growing to exceptional sizes, then Prionosuchus may well be one of the key apex predators of the Permian. This would mean that larger Prionosuchus would be able to attack and kill almost anything else in the water, even smaller members of their own species. It is also not impossible that they may have attacked land dwelling animals that came to the water to drink in a similar manner as modern day crocodiles, though it should be pointed out that there is no evidence for this.
A 1991 paper by C. B. Cox and P. Hutchinson came to the conclusion that Prionosuchus should be synonymised with the genus Platyoposaurus. A result of this study was that the Pedra do Fogo Formation in Brazil where Prionosuchus has been found was credited with being Mid-Late Permian in age. However, later study of the Pedra do Fogo Formation has confirmed that it is actually Middle Permian, and not of the same time as the deposits where Platyoposaurus has been found. Although the suggestion could be made that Platyoposaurus had an exceptionally long temporal range in the fossil record and that Prionosuchus should still be included with it, there is no supporting evidence for this. As a result, most researchers today prefer to keep Prionosuchus separate from Platyoposaurus, especially when the geographic gap between them is also considered.
- Um anfibio Labirinthodonte da formacao Pedra de Fogo, Estado do Maranhao - Ministerio da Agricultura, Departamento Nacional da Producao ineral Divisao de Geologia e Mineralogia, Boletim n. 124, p. 7-32. - L. I. Price - 1948.
- Fishes and amphibians from the Late Permian Pedra de Fogo Formation of Northern Brazil. - Palaeontology, 34(3): 561-573. - C. B. Cox & P. Hutchinson - 1991.
- Biological Scaling Problems and Solutions in Amphibians. - Cold Spring Harbor Perspectives in Biology, a019166. - D. L. Levy & R. Heald - 2015.