Two New Plioplatecarpine (Squamata, Mosasauridae) Genera from the Upper Cretaceous of North America, and a Global Phylogenetic Analysis of Plioplatecarpines [X1295] (matrix)

10.7934/x1295 ◽  
2014 ◽  
Author(s):  
K Konishi ◽  
W Caldwell
Keyword(s):  
Phylogenetic Analysis ◽  
North America ◽  
Upper Cretaceous

scholarly journals A new brachylophosaurin (Dinosauria: Hadrosauridae) from the Upper Cretaceous Menefee Formation of New Mexico

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11084 ◽  
Author(s):  
Andrew T. McDonald ◽  
Douglas G. Wolfe ◽  
Elizabeth A. Freedman Fowler ◽  
Terry A. Gates
Keyword(s):  
Phylogenetic Analysis ◽  
New Mexico ◽  
North America ◽  
Upper Cretaceous ◽  
Western North America ◽  
Caudal Region ◽  
Rostral Region ◽  
Partial Skeleton

Brachylophosaurini is a clade of hadrosaurid dinosaurs from the Campanian of western North America. Although well-known from northern localities in Montana and Alberta, including abundant material of Brachylophosaurus canadensis and Maiasaura peeblesorum and the holotypes of Acristavus gagslarsoni and Probrachylophosaurus bergei, material from southern localities in Utah and Colorado is restricted to a partial skull referred to A. gagslarsoni and several indeterminate specimens. Here we describe Ornatops incantatus gen. et sp. nov., a new brachylophosaurin known from a partial skeleton from the Allison Member of the Menefee Formation in New Mexico. Ornatops is the first brachylophosaurin reported from New Mexico and the southernmost occurrence of the clade. Ornatops shares with Probrachylophosaurus and Brachylophosaurus a caudally expanded nasofrontal suture on the frontals, but also exhibits an autapomorphic nasofrontal suture morphology, with a horizontal rostral region and elevated caudal region with two prominent parasagittal bumps, which is different from other brachylophosaurin specimens, including juvenile and adult Brachylophosaurus. A phylogenetic analysis places Ornatops in a trichotomy with Probrachylophosaurus and Brachylophosaurus, with Maiasaura and Acristavus as successive outgroups.

Neritoptyx hogansoninew species (Gastropoda, Mollusca) from the Upper Cretaceous Fox Hills Formation on the Dakota Isthmus, western United States

2018 ◽  
Vol 93 (2) ◽  
pp. 278-290
Author(s):  
J. Mark Erickson
Keyword(s):  
Heat Transfer ◽  
United States ◽  
New Species ◽  
North America ◽  
Upper Cretaceous ◽  
Gulf Coast ◽  
Western United States ◽  
Western Interior Seaway ◽  
Decapod Crustaceans ◽  
Upper Maastrichtian

AbstractIn midcontinent North America, the Fox Hills Formation (Upper Cretaceous, upper Maastrichtian) preserves the last marine faunas in the central Western Interior Seaway (WIS).Neritoptyx hogansoninew species, a small littoral snail, exhibited allometric change from smooth to corded ornament and rounded to shouldered shape during growth. Specimens preserve a zig-zag pigment pattern that changes to an axial pattern during growth.Neritoptyx hogansoninew species was preyed on by decapod crustaceans, and spent shells were occupied by pagurid crabs. Dead mollusk shells, particularly those ofCrassostrea subtrigonalis(Evans and Shumard, 1857), provided a hard substrate to which they adhered on the Fox Hills tidal flats. This new neritimorph gastropod establishes a paleogeographic and chronostratigraphic proxy for intertidal conditions on the Dakota Isthmus during the late Maastrichtian. Presence of a neritid extends the marine tropical/temperate boundary in the WIS northward to ~44° late Maastrichtian paleolatitude. Late Maastrichtian closure of the isthmus subsequently altered marine heat transfer by interrupting northward flow of tropical currents from the Gulf Coast by as much as 1 to 1.5 million years before the Cretaceous ended.UUID:http://zoobank.org/3ba56c07-fcca-4925-a2f0-df663fc3a06b

scholarly journals A New Ankylosaurid Dinosaur from the Upper Cretaceous (Kirtlandian) of New Mexico with Implications for Ankylosaurid Diversity in the Upper Cretaceous of Western North America

PLoS ONE ◽  
2014 ◽  
Vol 9 (9) ◽  
pp. e108804 ◽  
Author(s):  
Victoria M. Arbour ◽  
Michael E. Burns ◽  
Robert M. Sullivan ◽  
Spencer G. Lucas ◽  
Amanda K. Cantrell ◽  
...  
Keyword(s):  
New Mexico ◽  
North America ◽  
Upper Cretaceous ◽  
Western North America

Anatomical, morphometric, and stratigraphic analyses of theropod biodiversity in the Upper Cretaceous (Campanian) Dinosaur Park Formation

2021 ◽  
pp. 1-15
Author(s):  
Thomas M. Cullen ◽  
Lindsay Zanno ◽  
Derek W. Larson ◽  
Erinn Todd ◽  
Philip J. Currie ◽  
...  
Keyword(s):  
High Resolution ◽  
North America ◽  
Fossil Record ◽  
Upper Cretaceous ◽  
Environmental Changes ◽  
Morphometric Analyses ◽  
Variable Distribution ◽  
Taxic Diversity ◽  
Dinosaur Park Formation ◽  
Broad Scale

The Dinosaur Park Formation (DPF) of Alberta, Canada, has produced one of the most diverse dinosaur faunas, with the record favouring large-bodied taxa, in terms of number and completeness of skeletons. Although small theropods are well documented in the assemblage, taxonomic assessments are frequently based on isolated, fragmentary skeletal elements. Here we reassess DPF theropod biodiversity using morphological comparisons, high-resolution biostratigraphy, and morphometric analyses, with a focus on specimens/taxa originally described from isolated material. In addition to clarifying taxic diversity, we test whether DPF theropods preserve faunal zonation/turnover patterns similar to those previously documented for megaherbivores. Frontal bones referred to a therizinosaur (cf. Erlikosaurus), representing among the only skeletal record of the group from the Campanian–Maastrichtian (83–66 Ma) fossil record of North America, plot most closely to troodontids in morphospace, distinct from non-DPF therizinosaurs, a placement supported by a suite of troodontid anatomical frontal characters. Postcranial material referred to cf. Erlikosaurus in North America is also reviewed and found most similar in morphology to caenagnathids, rather than therizinosaurs. Among troodontids, we document considerable morphospace and biostratigraphic overlap between Stenonychosaurus and the recently described Latenivenatrix, as well as a variable distribution of putatively autapomorphic characters, calling the validity of the latter taxon into question. Biostratigraphically, there are no broad-scale patterns of faunal zonation similar to those previously documented in ornithischians from the DPF, with many theropods ranging throughout much of the formation and overlapping extensively, possibly reflecting a lack of sensitivity to environmental changes, or other cryptic ecological or evolutionary factors.

Deltatheroides—like mammals from the Upper Cretaceous of North America

Nature ◽  
1974 ◽  
Vol 249 (5455) ◽  
pp. 392-392 ◽  
Author(s):  
RICHARD C. FOX
Keyword(s):  
North America ◽  
Upper Cretaceous

scholarly journals First rebbachisaurid sauropod dinosaur from Asia

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246620
Author(s):  
Alexander Averianov ◽  
Hans-Dieter Sues
Keyword(s):  
Phylogenetic Analysis ◽  
Fossil Record ◽  
Upper Cretaceous ◽  
Neural Spine ◽  
Lateral Side ◽  
New Taxon ◽  
Caudal Vertebra

Dzharatitanis kingi gen. et sp. nov. is based on an isolated anterior caudal vertebra (USNM 538127) from the Upper Cretaceous (Turonian) Bissekty Formation at Dzharakuduk, Uzbekistan. Phylogenetic analysis places the new taxon within the diplodocoid clade Rebbachisauridae. This is the first rebbachisaurid reported from Asia and one of the youngest rebbachisaurids in the known fossil record. The caudal is characterized by a slightly opisthocoelous centrum, ‘wing-like’ transverse processes with large but shallow PRCDF and POCDF, and the absence of a hyposphenal ridge and of TPRL and TPOL. The neural spine has high SPRL, SPDL, SPOL, and POSL and is pneumatized. The apex of neural spine is transversely expanded and bears triangular lateral processes. The new taxon shares with Demandasaurus and the Wessex rebbachisaurid a high SPDL on the lateral side of the neural spine, separated from SPRL and SPOL. This possibly suggests derivation of Dzharatitanis from European rebbachisaurids. This is the second sauropod group identified in the assemblage of non-avian dinosaurs from the Bissekty Formation, in addition to a previously identified indeterminate titanosaurian.

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