A Late Triassic traversodont cynodont from the Newark Supergroup of North Carolina

1999 ◽  
Vol 19 (2) ◽  
pp. 351-354 ◽  
Author(s):  
Hans-Dieter Sues ◽  
Paul E. Olsen ◽  
Joseph G. Carter
Keyword(s):  
North Carolina ◽  
Late Triassic ◽  
Newark Supergroup

scholarly journals Diverse new microvertebrate assemblage from the Upper Triassic Cumnock Formation, Sanford Subbasin, North Carolina, USA

2012 ◽  
Vol 86 (2) ◽  
pp. 368-390 ◽  
Author(s):  
Andrew B. Heckert ◽  
Jonathan S. Mitchell ◽  
Vincent P. Schneider ◽  
Paul E. Olsen
Keyword(s):  
North Carolina ◽  
New Records ◽  
First Record ◽  
Upper Triassic ◽  
New Combination ◽  
Late Triassic ◽  
Small Juvenile ◽  
Lower Jaw ◽  
Newark Supergroup ◽  
Vertebrate Assemblage

The Moncure microvertebrate locality in the Cumnock Formation, Sanford sub-basin, North Carolina, dramatically increases the known Late Triassic age vertebrate assemblage from the Deep River Basin. The ∼50,000 recovered microvertebrate fossils include osteichthyans, amphibians, and numerous lepidosauromorph, archosauriform, and synapsid amniotes. Actinopterygian fossils consist of thousands of scales, teeth, skull, and lower jaw fragments, principally of redfieldiids and semionotids. Non-tetrapod sarcopterygians include the dipnoan Arganodus sp., the first record of lungfish in the Newark Supergroup. Temnospondyls are comparatively rare but the preserved centra, teeth, and skull fragments probably represent small (juvenile) metoposaurids. Two fragmentary teeth are assigned to the unusual reptile Colognathus obscurus (Case). Poorly preserved but intriguing records include acrodont and pleurodont jaw fragments tentatively assigned to lepidosaurs. Among the archosauriform teeth is a taxon distinct from R. callenderi that we assign to Revueltosaurus olseni new combination, a morphotype best assigned to cf. Galtonia, the first Newark Supergroup record of Crosbysaurus sp., and several other archosauriform tooth morphotypes, as well as grooved teeth assigned to the recently named species Uatchitodon schneideri. Synapsids represented by molariform teeth include both “traversodontids” assigned to aff. Boreogomphodon and the “dromatheriid” Microconodon. These records are biogeographically important, with many new records for the Cumnock Formation and/or the Newark Supergroup. In particular, Colognathus, Crosbysaurus, and Uatchitodon are known from basins of Adamanian age in the southwestern U.S.A. These new records include microvertebrate taxa more typical of non-Newark basins (abundant archosauriforms, temnospondyls, lungfish) as well as more typical Newark osteichthyans and synapsid-rich faunal elements.

scholarly journals Implications of the Newark Supergroup-based astrochronology and geomagnetic polarity time scale (Newark-APTS) for the tempo and mode of the early diversification of the Dinosauria

2010 ◽  
Vol 101 (3-4) ◽  
pp. 201-229 ◽  
Author(s):  
Paul E. Olsen ◽  
Dennis V. Kent ◽  
Jessica H. Whiteside
Keyword(s):  
Late Triassic ◽  
Eastern North America ◽  
Early Diversification ◽  
Chinle Formation ◽  
Distinct Genus ◽  
Low Diversity ◽  
Geomagnetic Polarity ◽  
Newark Supergroup ◽  
Geomagnetic Polarity Time Scale ◽  
Newark Basin

ABSTRACTThe Newark-APTS established a high-resolution framework for the Late Triassic and Early Jurassic. Palaeomagnetic polarity correlations to marine sections show that stage-level correlations of continental sequences were off by as much as 10 million years. New U–Pb ages show the new correlations and the Newark basin astrochronology to be accurate. Correlation of Newark-APTS to the Chinle Formation/Dockum Group, Glen Canyon Group, Fleming Fjord Formation and Ischigualasto Formation led to the following conclusions: (1) there are no unequivocal Carnian-age dinosaurs; (2) the Norian Age was characterised by a slowly increasing saurischian diversity but no unequivocal ornithischians; (3) there was profound Norian and Rhaetian continental provinciality; (4) the classic Chinle-, Germanic- and Los Colorados-type assemblages may have persisted to the close of the Rhaetian; (5) the distinct genus-level biotic transition traditionally correlated with the marine Carnian–Norian is in fact mid-Norian in age and within published error of the Manicouagan impact; (6) the end-Triassic marine and continental extinctions as seen in eastern North America were contemporaneous; and (7) compared to Triassic communities, Hettangian and Sinemurian age terrestrial communities were nearly globally homogenous and of low diversity. Consequently, the complex emerging picture of dinosaur diversification demands biostratigraphically-independent geochronologies in each of the faunally-important regions.

scholarly journals Under the armor: X-ray computed tomographic reconstruction of the internal skeleton ofCoahomasuchus chathamensis(Archosauria: Aetosauria) from the Upper Triassic of North Carolina, USA, and a phylogenetic analysis of Aetosauria

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4368 ◽  
Author(s):  
Devin K. Hoffman ◽  
Andrew B. Heckert ◽  
Lindsay E. Zanno
Keyword(s):  
North Carolina ◽  
Phylogenetic Analysis ◽  
Tomographic Reconstruction ◽  
Late Triassic ◽  
Recent Analysis ◽  
Appendicular Skeleton ◽  
Computed Tomographic ◽  
Holotype Specimen ◽  
X Ray Computed ◽  
The Right

Aetosauria is a clade of heavily armored, quadrupedal omnivorous to herbivorous archosaurs known from the Late Triassic across what was the supercontinent of Pangea. Their abundance in many deposits relative to the paucity of other Triassic herbivores indicates that they were key components of Late Triassic ecosystems. However, their evolutionary relationships remain contentious due, in large part, to their extensive dermal armor, which often obstructs observation of internal skeletal anatomy and limits access to potentially informative characters. In an attempt to address this problem we reanalyzed the holotype of a recently described species ofCoahomasuchus,C. chathamensis, from the Sanford sub-basin of North Carolina using computed tomography (CT). CT scans of the holotype specimen clarify preservation of the skeleton, revealing several articulated vertebrae and ribs, an isolated vertebra, left ulna, left scapula, and the right humerus, though none of the material resulted in updated phylogenetic scorings. Reexamination of aetosaur materials from the holotype locality also indicates that several isolated osteoderms and elements of the appendicular skeleton are newly referable. Based on these results, we update theCoahomasuchus chathamensishypodigm and conduct a revised phylogenetic analysis with improved character scorings forCoahomasuchusand several other aetosaurs. Our study recoversCoahomasuchusin a polytomy withAetosaurusand the Typothoracinae, in contrast with a recent analysis that recoveredCoahomasuchusas a wild-card taxon.

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