Redescription of Ankylosaurus magniventris Brown 1908 (Ankylosauridae) from the Upper Cretaceous of the Western Interior of North America

2004 ◽  
Vol 41 (8) ◽  
pp. 961-986 ◽  
Author(s):  
Kenneth Carpenter
Keyword(s):  
North America ◽  
Upper Cretaceous ◽  
The Body ◽  
Body Armor ◽  
Hell Creek Formation ◽  
South Central

The armor-plated dinosaur Ankylosaurus magniventris is redescribed based on specimens from the Hell Creek Formation of northeastern Montana, USA., Lance Formation of Wyoming, USA., and from the Scollard Formation of south-central Alberta, Canada. Except for brief descriptions, most of these specimens have not been described in detail. Ankylosaurus is one of the largest known ankylosaurids, having an estimated length of up to 6.25 m (20.5 ft). It is characterized by a long, low skull having very prominent cranial “horns” that project laterally or dorsolaterally. The body armor includes a large half-ring that sat across the base of the neck and shoulders and a large, low tail club.

New data on pachycephalosaurid dinosaurs (Reptilia: Ornithischia) from North America

1983 ◽  
Vol 20 (3) ◽  
pp. 462-472 ◽  
Author(s):  
Peter M. Galton ◽  
Hans-Dieter Sues
Keyword(s):  
United States ◽  
North America ◽  
Upper Cretaceous ◽  
New Genus ◽  
Biological Significance ◽  
The United States ◽  
Hell Creek Formation ◽  
Unusual Condition ◽  
Judith River Formation

In this paper several new significant specimens of pachycephalosaurid dinosaurs from Upper Cretaceous strata of Canada and the United States are described and figured. The domes of an unusual pachycephalosaurid from the Judith River Formation (Campanian) of Alberta show a slightly thickened frontal with an ornamentation of bony tubercles; they are referred to a new genus. A new genus of Pachycephalosauridae is described from the Hell Creek Formation (Maestrichtian) of Montana; it has horn-like projections on the squamosal. Sutural fusion between the quadrate and squamosal of Pachycephalosaurus is reported; this is an unusual condition among the Ornithischia. The biological significance of certain cranial features is considered.

New caenagnathid (Dinosauria: Theropoda) specimens from the Upper Cretaceous of North America and Asia

1993 ◽  
Vol 30 (10) ◽  
pp. 2255-2272 ◽  
Author(s):  
Philip J. Currie ◽  
Stephen J. Godfrey ◽  
Lev Nessov
Keyword(s):  
North America ◽  
South Dakota ◽  
Upper Cretaceous ◽  
New Genus ◽  
Food Type ◽  
New Genus And Species ◽  
Hell Creek Formation ◽  
Central Asian ◽  
Southern Alberta ◽  
Judith River Formation

New specimens of caenagnathid theropods are described from the Judith River Formation (Campanian) of southern Alberta, the Hell Creek Formation (Maastrichtian) of South Dakota, and the Bissekty Formation (Turonian) of Uzbekistan. With the exception of the Hell Creek specimen, and a vertebra from Alberta, all are from the symphysial regions of the lower jaws. Caenagnathids are rare and poorly known animals, and the described fossils preserve heretofore unknown features, including vascular grooves and foramina in the symphysial region, and the pattern of overlapping sutures between jaw elements. Most of the new specimens are different from the holotype of Caenagnathus collinsi Sternberg and may represent the second described species, Caenagnathus sternbergi. The two jaws from the Bissekty Formation are the first oviraptorosaurian jaws described from Uzbekistan and represent a new genus and species anatomically closer to Caenagnathus than to central Asian forms like Oviraptor, Conchoraptor and Ingenia. There are at least five characters that distinguish caenagnathid and oviraptorid jaws, but it is concluded that the length of the symphysial region must be used with caution. Jaw anatomy supports the idea that oviraptorids were well adapted for eating eggs, although their diet was probably not restricted to one food type.

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 THE NOCTUIDÆ OF EUROPE AND NORTH AMERICA.: (Third Paper.)

1889 ◽  
Vol 21 (10) ◽  
pp. 188-193
Author(s):  
A. R. Grote
Keyword(s):  
North America ◽  
The Body ◽  
European Species ◽  
Siberian Species

The tibiæ are usually all spinose, the eyes naked, the body untufted, the form normal, the male antennæ of various structure, pectinated, brushlike simple. The European species are refered by Lederer all to one genus, Agrotis or Hübner. Nervertheless, I think the yellow-winged forms may well be separated under Hiria and Tryphœna. Of these yellow-winged forms, with flattened abdomen, we have only one T. Chardinyi, from Anticosti and Maine, considered identical with the Siberian species of the same name, described orginally by Boisduval under Anarta.

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

An Early Burial from Gordon Creek, Colorado

1971 ◽  
Vol 36 (2) ◽  
pp. 170-182 ◽  
Author(s):  
David A. Breternitz ◽  
Alan C. Swedlund ◽  
Duane C. Anderson
Keyword(s):  
North America ◽  
Annual Meeting ◽  
Preliminary Report ◽  
Skeletal Remains ◽  
The Body ◽  
National Forest ◽  
Bone Material ◽  
The North ◽  
Northern Colorado ◽  
Early Human

AbstractAn isolated burial was excavated from the bank of a tributary of Gordon Creek, Roosevelt National Forest, northern Colorado. A preliminary report was prepared (D. Anderson 1966, 1967) but further analysis of the skeletal material and newly obtained cultural information add significantly to the documentation of the burial.The body of a woman, aged 25-30 years, was given primary interment in a pit coated with red ocher. The body was placed on its left side with the head to the north, was tightly flexed, and was also coated with red ocher. Burial accompaniments include a large precussion flaked biface or preform, a small biface used as a scraping tool, a hammerstone, an end scraper, a preform with fire pocks, cut and incised animal ribs, and a perforated elk incisor. A radiocarbon assay of bone material from the left ilium produced an age of 9700± 250 radiocarbon years: 7750 B.C. (GX-0530).No indications of habitation which might be associated with the burial were located in its immediate vicinity.A reconstruction of the burial ritual is attempted, and the skeletal remains are compared to other early human remains from North America.A summary of this paper was given at the 34th Annual Meeting of the Society for American Archaeology, May 3, 1969, in Milwaukee, Wisconsin.

Amia cf. pattersoni from the Paleocene Paskapoo Formation of Alberta

2000 ◽  
Vol 37 (1) ◽  
pp. 31-37 ◽  
Author(s):  
Lance Grande ◽  
Li Guo-Qing ◽  
Mark VH Wilson
Keyword(s):  
North America ◽  
Fish Fauna ◽  
Taxonomic Diversity ◽  
Geographic Range ◽  
Green River Formation ◽  
Early Eocene ◽  
Freshwater Teleost ◽  
Additional Material ◽  
Green River ◽  
South Central

A well-prepared anterior half of an amiid skull from the Late Paleocene Paskapoo Formation of south-central Alberta is described. The specimen is either very closely related to, or conspecific with, Amia pattersoni Grande and Bemis, 1998, from the Early Eocene Green River Formation of Wyoming. We leave the specimen as Amia cf. pattersoni until additional material is found to further clarify its relationships. Amia cf. pattersoni is the oldest known specimen clearly identifiable as belonging to the genus Amia (sensu Grande and Bemis, 1998), and the Paskapoo species extends the known geographic range of Amia both northward and westward. The fish assemblage of the Paskapoo Formation represents the most diverse freshwater Paleocene fish fauna known from North America. Based on comparisons of sample size and relative taxonomic diversity to the better known Green River Formation localities of Wyoming, we predict that further collecting will substantially increase the known diversity of the Paskapoo fauna. The Paskapoo Formation, therefore, has great potential to continue adding to the meager knowledge of pre-Eocene freshwater teleost diversity in North America.

Paleomagnetism of the Triassic Nikolai Greenstone, McCarthy Quadrangle, Alaska

1977 ◽  
Vol 14 (11) ◽  
pp. 2578-2592 ◽  
Author(s):  
J. W. Hillhouse
Keyword(s):  
British Columbia ◽  
High Temperature ◽  
North America ◽  
Vertical Axis ◽  
Upper Triassic ◽  
Present Position ◽  
Stable Component ◽  
South Central ◽  
Early Mesozoic ◽  
Lamellar Texture

Paleomagnetic evidence indicates that the extensive early Mesozoic basalt field near McCarthy, south-central Alaska, originated far south of its present position relative to North America. Results obtained from the Middle and (or) Upper Triassic Nikolai Greenstone suggest that those basalts originated within 15° of the paleoequator. This position is at least 27° (3000 km) south of the Upper Triassic latitude predicted for McCarthy on the basis of paleomagnetic data from continental North America. The Nikolai pole, as determined from 50 flows sampled at 5 sites, is at 2.2° N, 146.1° E (α95 = 4.8°). The polarity of the pole is ambiguous, because the corresponding magnetic direction has a low inclination and a westerly declination. Therefore, the Nikolai may have originated near 15° N latitude or, alternatively, as far south as 15° S latitude. In addition to being displaced northward, the Nikolai block has been rotated roughly 90° about the vertical axis. A measure of the reliability of this pole is provided by favorable results from the following tests: (1) Within one stratigraphic section, normal and reversed directions from consecutive flows are antipolar. (2) Consistent directions were obtained from sites 30 km apart. (3) Application of the fold test indicated the magnetization was acquired before the rocks were folded. (4) The magnetizations of several pilot specimens are thermally stable up to 550 °C. The stable component is probably carried by magnetite with lamellar texture, a primary feature commonly acquired by a basalt at high temperature during initial cooling of the magma. Geologic and paleomagnetic evidence indicates that the Nikolai is allochthonous to Alaska and that, together with associated formations in southern Alaska and British Columbia, it is part of a now disrupted equatorial terrane.

Sierraceratops turneri, a new chasmosaurine ceratopsid from the Hall Lake Formation (Upper Cretaceous) of south-central New Mexico

2021 ◽  
pp. 105034
Author(s):  
Sebastian G. Dalman ◽  
Spencer G. Lucas ◽  
Steven E. Jasinski ◽  
Nicholas R. Longrich
Keyword(s):  
New Mexico ◽  
Upper Cretaceous ◽  
South Central ◽  
Lake Formation
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