Prozostrodon brasiliensis, a probainognathian cynodont from the Late Triassic of Brazil: second record and improvements on its dental anatomy

  title={Prozostrodon brasiliensis, a probainognathian cynodont from the Late Triassic of Brazil: second record and improvements on its dental anatomy},
  author={Cristian Pereira Pacheco and Agustín G. Martinelli and Ane E B Pavanatto and Marina Bento Soares and S{\'e}rgio Dias-da-silva},
  journal={Historical Biology},
  pages={475 - 485}
Abstract Probainognathian cynodonts are conspicuous elements of the Assemblage Zones of the Triassic Santa Maria Supersequence in southern Brazil. Within this group, the derived clade Prozostrodontia, in which the crown group Mammalia is included, is taxonomic diverse in the Hyperodapedon and Riograndia AZs. We describe here the second known specimen (CAPPA/UFSM 0123) of Prozostrodon brasiliensis, until now only represented by its holotype. CAPPA/UFSM 0123 includes a right dentary with… 

A New Prozostrodontian Cynodont (Eucynodontia, Probainognathia) from the Upper Triassic of Southern Brazil

ABSTRACT Probainognathian cynodonts are well represented in the fossil record from the Middle and Upper Triassic of South America, especially in Brazil and Argentina. In this contribution, we

A new cynodont from the Santa Maria formation, south Brazil, improves Late Triassic probainognathian diversity

The fossil record of non‐mammaliaform probainognathian cynodonts is outstanding in the Late Triassic rocks of Brazil and Argentina. Approximately 15 genera are known, providing unique insights in the

Bortolin site, a new fossiliferous locality in the Triassic (Ladinian/Carnian) of southern Brazil

A new fossiliferous site from the Pinheiros-Chiniqua Sequence (Santa Maria Supersequence) with typical tetrapod components of the Dinodontosaurus Assemblage Zone (AZ) is here described. The new site

New sauropodomorph and cynodont remains from the Late Triassic Sacisaurus site in southern Brazil and its stratigraphic position in the Norian Caturrita Formation

Sacisaurus agudoensis is the only silesaurid known from the Triassic beds of the Santa Maria Supersequence and the correlation of its type locality to the other Triassic deposits of south Brazil has

Gnathovorax cabreirai: a new early dinosaur and the origin and initial radiation of predatory dinosaurs

An ecomorphological analysis employing dental traits indicates that herrerasaurids occupy a particular area in the morphospace of faunivorous dinosaurs, which partially overlaps the area occupied by post-Carnian theropods, indicating that her rerasaurid dinosaurs preceded the ecological role that later would be occupied by large to medium-sized theropoda.

A proposed terminology for the dentition of gomphodont cynodonts and dental morphology in Diademodontidae and Trirachodontidae

A comprehensive description of the dentition of each diademodontid and trirachodontids species, as well as detailed illustrations of each dental unit, are presented after firsthand examination of material and 3D reconstructions of postcanine teeth.

The Late Triassic Record of Cynodonts: Time of Innovations in the Mammalian Lineage

The Late Triassic constitutes a pivotal time lapse, marked by an expansion of the geographical distribution and diversification of cynodonts, and summarizes the main morphologies represented in the lineage, including Mammaliaformes, a key group in the authors' understanding of the early evolution of mammals.

The Evolution of the Maxillary Canal in Probainognathia (Cynodontia, Synapsida): Reassessment of the Homology of the Infraorbital Foramen in Mammalian Ancestors

This study finds that the mammalian condition is the result of a gradual shortening of the maxillary canal, which enabled the infraorbital nerve to ramify within the soft tissues of the face.



A new tritheledontid (Therapsida, Eucynodontia) from the Late Triassic of Rio Grande do Sul (Brazil) and its phylogenetic relationships among carnivorous non-mammalian eucynodonts

The presence of two kinds of upper postcanines in different replacement waves in Irajatherium could be a useful feature for inference of possible mechanism of dental differentiation among non-mammalian cynodonts.

Trucidocynodon riograndensis gen. nov. et sp. nov. (Eucynodontia), a new cynodont from the Brazilian Upper Triassic (Santa Maria Formation)

An almost complete skeleton of a new carnivorous cynodont from the Upper Triassic of Southern Brazil, Trucidocynodon riograndensis gen. nov., is described and the overall morphology of the astragalocalcaneal complex is similar to that of Diademodon and of the therocephalian Bauria.

Two New Cynodonts (Therapsida) from the Middle-Early Late Triassic of Brazil and Comments on South American Probainognathians

Two new cynodonts from the early Late Triassic of southern Brazil are described and the phylogenetic hypothesis presented herein indicates the degree to which knowledge on probainognathian cynodronts is incomplete and also the relevance of the South American fossil record for understanding their evolutionary significance.

A new species of the traversodontid cynodont Exaeretodon from the Santa Maria Formation (Middle/Late Triassic) of southern Brazil

The presence of prootic crests in the extensive lateral flange, anterior to the fenestra ovalis, is a noteworthy basicranial trait, unique to this new taxon among non-mammalian cynodonts.

A new carnivorous cynodont from the Ischigualasto Formation (Late Triassic, Argentina), with comments on eucynodont phylogeny

ABSTRACT The nearly complete skull of a recently discovered carnivorous eucynodont, Ecteninion lunensis, gen. et sp. nov., is described. This is the first new genus of carnivorous cynodont reported

New information about Irajatherium hernandezi Martinelli, Bonaparte, Schultz & Rubert 2005 (Eucynodontia, Tritheledontidae) from the upper triassic (Caturrita Formation, Paraná Basin) of Brazil

In this contribution, new specimens of the tritheledontid eucynodont Irajatherium hernandezi, from the Late Triassic (Caturrita Formation) of southern Brazil, are analyzed. The new material provides

The lower jaw and dentition of the traversodontid Exaeretodon riograndensis Abdala, Barberena & Dornelles, from the Brazilian Triassic (Santa Maria 2 Sequence, Hyperodapedon Assemblage Zone)

The first fairly complete postdentary series of the mandible of E. riograndensis is described and additional information on its lower dentition is provided to improve the understanding of the anatomy of the Brazilian species.

Chiniquodontid cynodonts: systematic and morphometric considerations

Allometric analysis of chiniquodontids sensu stricto reveals that all specimens can be confidently arranged in a single growth series, irrespective of their original species assignments; and most of the measurements change isometrically with respect to skull length.


A cladistic analysis of ictidosaurians supports its monophyly and indicates that they represent an ancestral condition that facilitated the development of the mammalian skull base constituted by the reduced pterygoids, the basisphenoid, and posteriorly thedevelopment of the presphenoid by the ventral extension of the braincase.

The presence of Compsocerops (Brachyopoidea: Chigutisauridae) (Late Triassic) in southern Brazil with comments on chigutisaurid palaeobiogeography

Abstract:  Chigutisauridae is the longest‐lived trematosaurian clade (from early Triassic to early Cretaceous). They were reported in Argentina, Australia, India and South Africa. This contribution