Early Evolutionary History of the Synapsida

  title={Early Evolutionary History of the Synapsida},
  author={Christian F. Kammerer and K. D. Angielczyk and J{\"o}rg Fr{\"o}bisch},
  journal={Early Evolutionary History of the Synapsida},
An exceptionally well-preserved specimen of the bauriid therocephalian Microgomphodon oligocynus from the Burgersdorp Formation (Early-Middle Triassic, Cynognathus Assemblage Zone) of the South African Karoo is described. In addition, a taxonomic revision of bauriid therocephalians from southern Africa, based on firsthand examination of almost all know specimens, is presented. Microgomphodon oligocynus and Bauria cynops are recognized as the only valid species of southern African bauriids… 
Adult morphology of the therocephalian Simorhinella baini from the middle Permian of South Africa and the taxonomy, paleobiogeography, and temporal distribution of the Lycosuchidae
The skull and partial skeleton of a large therocephalian from the uppermost Tapinocephalus Assemblage Zone of South Africa is described and forms the basis for a taxonomic re-evaluation of the Lycosuchidae as well as of the geographic and stratigraphic range of the family.
Revision of the first therocephalian, Theriognathus Owen (Therapsida: Whaitsiidae), and implications for cranial ontogeny and allometry in nonmammaliaform eutheriodonts
The results suggest that the single species, Theriognathus microps, represented one of the most abundant Late Permian therocephalians in southern Africa and is consequently a potentially useful biostratigraphic marker for the upper Cistecephalus-lower Dicynodon Assemblage Zone transition (i.e., late Wuchiapingian).
A New Large Gomphodont from the Triassic of South Africa and Its Implications for Gondwanan Biostratigraphy
ABSTRACT A partial skull (BP/1/7976) of a very large cynodont from the Middle Triassic Cynognathus Assemblage Zone (Cricodon-Ufudocyclops subzone) of South Africa is described. The specimen
A Re-Description of ‘Mycterosaurus’ smithae, an Early Permian Eothyridid, and Its Impact on the Phylogeny of Pelycosaurian-Grade Synapsids
An expanded version of a recently published phylogenetic analysis of pelycosaurian-grade synapsids positions Vaughnictis as the sister taxon of Eothyris within the clade Eothirididae, and confirms the recently-disputed position of caseasaurs as the most basal synapsid.
New information on the postcranial skeleton of Massetognathus ochagaviae Barberena, 1981 (Eucynodontia, Traversodontidae), from the Middle Triassic of Southern Brazil
Abstract New postcranial remains of Massetognathus ochagaviae are described based on a new specimen collected at the Dinodontosaurus Assemblage Zone from the Middle Triassic of Southern Brazil.
Cranial anatomy of the gorgonopsian Cynariops robustus based on CT-reconstruction
Inclusion of Cynariops in a phylogenetic analysis of Gorgonopsia recovers it within a large clade of African taxa, more closely related to Lycaenops and rubidgeines than Eriphostoma or Gorg onops.
Taxonomy of the proterosuchid archosauriforms (Diapsida: Archosauromorpha) from the earliest Triassic of South Africa, and implications for the early archosauriform radiation
It is concluded that the holotype of Proterosuchus fergusi is undiagnostic, and a neotype is proposed for the species, suggesting a greater species richness of earliest Triassic archosauriforms than previously appreciated.
A New Eutherocephalian (Therapsida, Therocephalia) from the Upper Permian Madumabisa Mudstone Formation (Luangwa Basin) of Zambia
The new therocephalian therapsid Ichibengops munyamadziensis adds to a list of sister-group pairs of Wuchiapingian tetrapods in southern Gondwana and Laurasia, indicating that effective, though largely unknown, dispersal routes persisted in Pangea at least through early late Permian times.
On the Validity and Phylogenetic Position of Eubrachiosaurus browni, a Kannemeyeriiform Dicynodont (Anomodontia) from Triassic North America
Inclusion of Eubrachiosaurus in a revised phylogenetic analysis of anomodont therapsids indicates that it is a stahleckeriid closely related to the South American genera Ischigualastia and Jachaleria, which alters perception of Late Triassic dicynodont diversity in the northern hemisphere.
Cranial osteology of Arctognathus curvimola, a short‐snouted gorgonopsian from the Late Permian of South Africa
The South African gorgonopsian species Arctognathus curvimola is redescribed based on a well-preserved skull and Autapomorphies identified for A. curvimola include a characteristic curvature to the alveolar margin of the snout, extremely reduced lacrimal, lengthy upper postcanine tooth row and a unique vomerine morphology.


Consideration of qualitative characters together with the allometric results lead to the conclusion that all forms belong to a single species in a growth series, and Massetognathus pascuali is recognized as the only valid entity.
A new skeleton of the therocephalian synapsid Olivierosuchus parringtoni from the Lower Triassic South African Karoo Basin
Abstract:  We provide a redescription of the therocephalian therapsid Olivierosuchus parringtoni based on a new specimen recovered from the Lower Triassic Lystrosaurus Assemblage Zone of South Africa
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
The cranial anatomy of Kombuisia frerensis Hotton (Synapsida, Dicynodontia) and a new phylogeny of anomodont therapsids
The general topology of this phylogeny supports the main aspects of recent hypotheses of anomodont relationships, and not only resolves critical nodes at the base of the Dicynodontia that were previously obscured by polytomies, but also introduces new hypotheses of relationships.
Cranial Anatomy of Ennatosaurus tecton (Synapsida: Caseidae) from the Middle Permian of Russia and the Evolutionary Relationships of Caseidae
Phylogenetic analysis of Caseidae yields a single most parsimonious tree and its topology reveals that the pattern of dental complexity in terms of the number of apical cuspules is homoplasious, cautioning against its use as a unidirectional phylogenetic character.
The last “pelycosaur”: a varanopid synapsid from the Pristerognathus Assemblage Zone, Middle Permian of South Africa
We report on a partial varanopid skull and mandible from the Pristerognathus Assemblage Zone of the Beaufort Group, in the South African Karoo Basin, which is probably latest Middle Permian
Anatomy and Phylogenetic Relationships of Boreogomphodon jeffersoni (Cynodontia: Gomphodontia) from the Upper Triassic of Virginia
Phylogenetic analysis suggests the existence of a clade comprising Boreogomphodon plus two other taxa in the Northern Hemisphere that is the sister group to most other known Middle and Late Triassic traversodonts from Gondwana.
A New Species of Emydops (Synapsida, Anomodontia) and a Discussion of Dental Variability and Pathology in Dicynodonts
Phylogenetic analysis supports the sister-taxon relationship of the two species of Emydops and their position at the base of E mydopidae, and concludes that E. oweni has both tusked and tuskless morphs.
Abstract The dicynodont species “Cryptocynodon” parringtoni von Huene, 1942 was described from a single poorly preserved specimen collected from the Upper Permian Kawinga Formation, Ruhuhu Basin,
A New Specimen of Promoschorhynchus (Therapsida: Therocephalia: Akidnognathidae) from the Lower Triassic of South Africa and its Implications for Theriodont Survivorship Across the Permo-Triassic Boundary
ABSTRACT The anatomy of a new subadult specimen of eutherocephalian therapsid, attributed to Promoschorhynchus cf. P. platyrhinus, is described from lowermost Triassic Lystrosaurus Assemblage Zone