A New Nonmammalian Eucynodont (Synapsida: Therapsida) from the Triassic of Northern Gansu Province, China, and its Biostratigraphic and Biogeographic Implications

  title={A New Nonmammalian Eucynodont (Synapsida: Therapsida) from the Triassic of Northern Gansu Province, China, and its Biostratigraphic and Biogeographic Implications},
  author={Keqin Gao and Richard C. Fox and Chang-Fu Zhou and Da-Qing Li},
Abstract A new trirachodontid eucynodont, Beishanodon youngi, is named and described based on a well-preserved skull from Triassic lacustrine deposits exposed in the Beishan Hills, northern Gansu Province, China. The new discovery documents the second record of trirachodontid eucynodonts known from China, along with Sinognathus gracilis from the Middle Triassic Ermaying Formation exposed in Shanxi Province. Cladistic analysis supports the placement of the new taxon as the sister group of… 
A new scanilepiform from the Lower Triassic of northern Gansu Province, China, and phylogenetic relationships of non‐teleostean Actinopterygii
A new scanilepiform, Beishanichthys brevicaudalis gen. et sp. nov., is named and described based on fossils from the Lower Triassic lake deposits exposed in Beishan area, Gansu Province, China. The
Taxonomic Revision of Plesiofuro mingshuica from the Lower Triassic of Northern Gansu, China, and the Relationships of Early Neopterygian Clades
A taxonomic revision of Plesiofuro mingshuica is provided based on a comparative study including over 500 new specimens and sheds new light on one of the least resolved areas of osteichthyan phylogeny: the so-called ‘subholosteans’ of the neopterygian total group.
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
Angonisaurus and Shansiodon, Dicynodonts (Therapsida, Anomodontia) from Subzone C of the Cynognathus Assemblage Zone (Middle Triassic) of South Africa
ABSTRACT Dicynodonts are the most abundant therapsids from the Beaufort Group (Karoo Basin, South Africa), and they have been used as index fossils to define most of the Beaufort biozones. Although
Cricodon metabolus (cynodontia: Gomphodontia) from the Triassic Ntawere Formation of Northeastern Zambia: Patterns of Tooth replacement and a Systematic Review of the Trirachodontidae
  • C. Sidor, J. Hopson
  • Biology, Environmental Science
    Journal of Vertebrate Paleontology
  • 2017
It is suggested that the two reputed trirachodontids from China might be probainognathians that convergently evolved expanded postcanine teeth rather than gomphodontians.
Ontogeny in the Malagasy Traversodontid Dadadon isaloi and a Reconsideration of its Phylogenetic Relationships
Denticulated incisors evolved multiple times in traversodontid evolution (in massetognathines and Arctotraversodon), and thus this group represents another possibility (besides various archosauromorphs) to be considered when attempting to identify isolated Triassic teeth with denticulated carinae lacking cingula.
Craniofacial Morphology of Vintana Sertichi (Mammalia, Gondwanatheria) from the Late Cretaceous of Madagascar
ABSTRACT The Gondwanatheria are an enigmatic clade of Cretaceous and Paleogene mammals known from South America, Africa, Madagascar, India, and the Antarctic Peninsula. The eight valid species—each
The Traversodontid Cynodont Mandagomphodon hirschsoni from the Middle Triassic of the Ruhuhu Valley, Tanzania
Mandagomphodon hirschsoni (gen. nov., comb. nov.) is one of three species of traversodontid cynodont placed in Scalenodon [type species S. angustifrons (Parrington, 1946)] by Crompton (1972). It is
A new traversodontid cynodont with a peculiar postcanine dentition from the Middle/Late Triassic of Namibia and dental evolution in basal gomphodonts
Dentition evolution in basal cynognathians likely resulted from three shifts in feeding ecologies, from a carnivorous to an omnivorous diet in basal-most gomphodonts, followed by an adaptation to a specialized feeding ecology possibly made of insects and hard plant material in traditional ‘trirachodontids’, then an increase in the consumption of plant-material in basal traversodontidae.
Virtual reconstruction of cranial endocasts of traversodontid cynodonts (Eucynodontia: Gomphodontia) from the upper Triassic of Southern Brazil
The brain endocasts of the late Triassic traversodontids Siriusgnathus niemeyerorum and Exaeretodon riograndensis from southern Brazil are described based on virtual models generated using computed tomography scan data, showing an endocranial cavity that is not fully ossified.


A new trirachodontid cynodont from the lower levels of the Burgersdorp Formation (Lower Triassic) of the Beaufort Group, South Africa and the cladistic relationships of Gondwanan gomphodonts
A new trirachodontid cynodont is described from the base of the Burgersdorp Formation (Subzone A fauna of the Cynognathus Assemblage Zone), of the South African Karoo Basin and is characterized by circular to ovoid in outline upper postcanines and the absence of a maxillary platform lateral to the postcanine series.
New Material Of Menadon besairiei (Cynodontia: Traversodontidae) From the Triassic Of Madagascar
A phylogenetic analysis incorporating information from the new specimens supports the placement of Menadon as the sister taxon to the clade Exaeretodon + Scalenodontoides, and shows that this taxon had a well-developed internarial bar and four upper incisors.
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
On some Triassic cynodonts from Tanganyika
It has been concluded that the Triassic cynodonts of the Ruhuhu valley compare more closely with those of the Brazilian Rio do Rasto Series than withThose of South African deposits.
Evolutionary Patterns Among Permo-Triassic Therapsids*
Synapsids form the bulk of tetrapod diversity from Early Permian to Middle Triassic times and thus can provide critical information on the nature of the Permo-Triassic extinction in the terrestrial realm.
Morphology and systematics of the northern Dvina Cynodonts lReptiliac Therapsidas upper Permianr
The morphological peculiarities of this Northern Dvina cynodont justify its being set apart in a separate family Dviniidae related to the Procynosuchidae — the extremely primitive Cynodonts of South Africa.
Whaitsiid Therocephalia and the origin of cynodonts
It is argued that the organization of the cynodont skull can be seen as a logical functional development from the more primitive condition, and in particular, the streptostylic nature of the jaw articulation, the enlargement of the dentary and reduction of the postdentary bones, may all be correlated with the development of a masseter muscle.
Growth and life habits of the Triassic cynodont Trirachodon, inferred from bone histology
The bone histology of all the elements consists of a moderately vascularized, periodically interrupted, fibro−lamellar bone tissue, which suggests that the overall growth of Trirachodon was probably rapid during the favourable season, but decreased or ceased during the unfavourable season.
The Osteology of the Reptiles
IN no domain of zoological science have the con tributions of American naturalists been more splendid than in that of vertebrate palaeontology, and in the list of pioneer workers in this domain an