Peirosaurids

Peirosaurids are an extinct family of crocodyliform reptiles belonging to the clade Notosuchia. They are known from Cretaceous rocks and are among the better documented notosuchians from Gondwana. Fossils have been reported primarily from South America, with additional records from Africa, indicating a distribution that spanned several landmasses of the ancient southern continents. The temporal range spans from the Early to Late Cretaceous, though the completeness of the record means exact dates vary by specimen.

In terms of appearance and ecology, peirosaurids were generally small to medium-sized crocodyliforms with elongated snouts. Their skulls and teeth show a range of shapes, reflecting a carnivorous and possibly omnivorous diet. Compared with modern crocodylians, many notosuchians, including peirosaurids, were thought to be more terrestrial or semi-aquatic, occupying a variety of ecological niches. The dental diversity within the group suggests different feeding strategies among genera and species.

Notable genera include Peirosaurus, described from Brazil, and Uberabasuchus vilabai, also from Brazil. These taxa illustrate the early diversification of notosuchians in South America during the Cretaceous. Peirosaurids are typically discussed within the broader notosuchian framework, and their precise relationships to other notosuchian families have shifted with new analyses and discoveries.

Taxonomically, peirosaurids are placed within Notosuchia, often under the informal grouping Peirosauroidea. However, phylogenetic relationships among notosuchians remain a topic of ongoing research, and the placement of peirosaurids may be revised as new fossils are found and reassessed. Peirosaurids thus contribute to understanding the diversity and evolutionary history of Gondwanan crocodyliforms in the Cretaceous.