Terlinguachelys fischbecki, a new genus and species of sea turtle (Chelonioidea: Protostegidae) from the Upper Cretaceous of Texas

2004 ◽  
Vol 78 (6) ◽  
pp. 1163-1178 ◽  
Author(s):  
Thomas M. Lehman ◽  
Susan L. Tomlinson
Keyword(s):  
National Park ◽  
Upper Cretaceous ◽  
New Genus ◽  
Sea Turtles ◽  
Sea Turtle ◽  
Unique Combination ◽  
New Genus And Species ◽  
Big Bend National Park ◽  
Big Bend ◽  
Lower Jaw

Remains of a large sea turtle, Terlinguachelys fischbecki n. gen. and sp., were recovered from paralic deposits of the Upper Cretaceous (Campanian) Aguja Formation in Big Bend National Park, Texas. T. fischbecki is a primitive protostegid that retains a constricted humerus, well ossified plastron and costals, prominent retroarticular process on the lower jaw, and long slender femora; however, it has some features, such as a prominent tubercle at the base of the scapular acromion process, found elsewhere only in derived leatherback sea turtles. The unique combination of primitive and derived traits in T. fischbecki illustrates further diversity among Cretaceous sea turtles and another case of parallelism common in sea turtle phylogeny.

Tyrannosauroid dinosaurs from the Aguja Formation (Upper Cretaceous) of Big Bend National Park, Texas

2012 ◽  
Vol 103 (3-4) ◽  
pp. 471-485 ◽  
Author(s):  
Thomas M. Lehman ◽  
Steven L. Wick
Keyword(s):  
National Park ◽  
Upper Cretaceous ◽  
Frontal Bone ◽  
Adult Size ◽  
Unique Combination ◽  
Big Bend National Park ◽  
West Texas ◽  
Big Bend ◽  
Large Predators ◽  
Sagittal Crest

ABSTRACTRare remains of tyrannosauroid dinosaurs from the Aguja Formation in West Texas indicate the presence here of a relatively gracile species, comparable in form and adult size to Appalachiosaurus or subadult albertosaurines, Gorgosaurus and Albertosaurus. Histologic analysis of one of the specimens indicates that the Aguja tyrannosaur attained an adult size substantially smaller than adult albertosaurines (700 kg, 6·5 m body length). The frontal bone is narrow with a wide orbital slot and a bipartite joint for the postorbital, features thought to be diagnostic of Albertosaurinae; but there is a tall sagittal crest and reduced parietal wedge separating the frontals on the midline, features thought to be diagnostic of Tyrannosaurinae. The tall sagittal crest may be a synapomorphy of Tyrannosaurinae, and the Aguja tyrannosaur is herein referred to that clade. However, the unique combination of character states exhibited by the frontal prevents confident attribution to any known species. The Aguja tyrannosaur provides further evidence that North American Campanian tyrannosauroids were remarkably diverse for such large predators, and that each species was apparently endemic to a relatively small geographic province.

scholarly journals The Boquillas Formation of the Big Bend National Park, Texas, USA, a reference Cenomanian through Santonian (Upper Cretaceous) carbonate succession at the southern end of the Western Interior Seaway

2017 ◽  
Vol 67 (4) ◽  
pp. 547-565 ◽  
Author(s):  
Dee Ann Cooper ◽  
Roger W. Cooper ◽  
James B. Stevens ◽  
M.S. Stevens ◽  
William A. Cobban ◽  
...  
Keyword(s):  
Marine Environment ◽  
National Park ◽  
Upper Cretaceous ◽  
Western Interior Seaway ◽  
Big Bend National Park ◽  
Big Bend ◽  
Marine Carbonate ◽  
Big Bend Region ◽  
C 78

Abstract The upper lower Cenomanian through middle Santonian (Upper Cretaceous) of the Boquillas Formation in the Big Bend Region of Trans-Pecos Texas consists of a marine carbonate succession deposited at the southern end of the Western Interior Seaway. The Boquillas Formation, subdivided into the lower, c. 78 m thick limestone-shale Ernst Member, and the upper, c. 132 m thick limestone/chalk/marl San Vicente Member, was deposited in a shallow shelf open marine environment at the junction between the Western Interior Seaway and the western margins of the Tethys Basin. Biogeographically, the area was closely tied with the southern Western Interior Seaway. The richly fossiliferous upper Turonian, Coniacian and lower Santonian parts of the Boquillas Formation are particularly promising for multistratigraphic studies.

scholarly journals A new nodosaurid ankylosaur (Dinosauria: Thyreophora) from the Upper Cretaceous Menefee Formation of New Mexico

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5435 ◽  
Author(s):  
Andrew T. McDonald ◽  
Douglas G. Wolfe
Keyword(s):  
New Mexico ◽  
Fossil Record ◽  
Upper Cretaceous ◽  
New Genus ◽  
Western United States ◽  
Unique Combination ◽  
New Genus And Species ◽  
San Juan Basin ◽  
History Of ◽  
Lower Campanian

Nodosauridae is a clade of armored dinosaurs with a rich fossil record and long history of study in North America. Nodosaurid fossils have been collected throughout the western United States and Canada. Here, we report three new nodosaurid specimens from the Upper Cretaceous (lower Campanian) Allison Member of the Menefee Formation, San Juan Basin, northwestern New Mexico. The three specimens belong to a new genus and species,Invictarx zephyri, characterized by a unique combination of features pertaining to the morphology of the osteoderms. Among the three specimens there are representative cervical/pectoral and thoracic osteoderms, as well as components of a probable co-ossified pelvic shield. The new tax on is most similar toGlyptodontopelta mimusfrom the Maastrichtian of New Mexico.

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