Early Campanian Multituberculates (Mammalia: Allotheria) from the Upper Milk River Formation, Alberta

1971 ◽  
Vol 8 (8) ◽  
pp. 916-938 ◽  
Author(s):  
Richard C. Fox
Keyword(s):  
Late Cretaceous ◽  
North American ◽  
Upper Cretaceous ◽  
Sampling Error ◽  
Taxonomic Diversity ◽  
New Genus And Species ◽  
The North ◽  
Evolutionary Radiation ◽  
Mammalian Teeth ◽  
Milk River Formation

Mammalian teeth collected from the early Campanian Upper Milk River Formation, southernmost Alberta, document a hitherto unknown evolutionary radiation of Late Cretaceous ptilodontoid and taeniolabidoid multituberculates. New species of the ectypodontids Mesodma and Cimexomys, the ptilodontid Cimolodon, and the cimolomyid Meniscoessus are defined, and teeth possibly pertaining to a second species of Mesodma and two species of Cimolomys are described. A new genus and species with uncertain relationships to known multituberculate families, is tentatively classified in the Taeniolabidoidea. Among North American Late Cretaceous multituberculates, at least Mesodma, Cimexomys, Cimolodon, Cimolomys, and Meniscoessus are seen to be evolutionarily conservative during early Campanian to late Maestrichtian times. The effects of sampling error on relative taxonomic diversity at horizons in the North American Upper Cretaceous are discussed.

Late Cretaceous gastropods from the Izumi Group of southwest Japan

1990 ◽  
Vol 64 (4) ◽  
pp. 563-578 ◽  
Author(s):  
Tomoki Kase
Keyword(s):  
Late Cretaceous ◽  
North American ◽  
Upper Cretaceous ◽  
Coastal Areas ◽  
Basal Part ◽  
Northwestern Pacific ◽  
New Genera ◽  
Southwest Japan ◽  
The North ◽  
The Family

The basal part of the Upper Cretaceous, mid-Campanian to Maastrichtian Izumi Group of the Izumi Mountains and Awaji Island, Southwest Japan, contains the most diverse gastropod fauna of this age in Japan. This paper discriminates 19 species and describes two new genera: Atira tricarinata n. sp., Ataphrus (s.s.) sp. A, Ataphrus (s.s.) sp. B, Globularia (s.s.) izumiensis n. sp., Lysis izumiensis n. sp., Trichotropis? sp., Deussenia takinoikensis n. sp., Volutilithes antiqua n. sp., Pseudoperissitys bicarinata Nagao and Otatume, Nekewis sp., Nipponitys inouei n. gen. and sp., Nipponitys acutangularis n. gen. and sp., Nipponitys sp. cf. N. magna (Kalishevitsch), Calorebama cretacea n. sp., Taniella japonica n. gen. and sp., Amuletum (s.s.) sp., Biplica osakensis n. sp., Biplica sphaerica n. sp., and Cylichna sp. The family Ampullospiridae is assigned to the suborder Architaenioglossa from the superfamily Naticacea. The enigmatic genus Lysis is tentatively assigned to the Calyptraeidae. Taniella japonica n. sp. is the oldest member of the family Olividae, and Calorebama cretacea n. sp. is the oldest member of the subfamily Pseudolivinae. Occurrence of Atira, Ataphrus, Biplica, and five perissityids further supports close communication of the northwestern Pacific Late Cretaceous gastropod faunas with those of the North American Pacific coastal areas.

Systematics and taxonomic diversity of squamates from the Upper Cretaceous Djadochta Formation, Bayan Mandahu, Gobi Desert, People's Republic of China

1996 ◽  
Vol 33 (4) ◽  
pp. 578-598 ◽  
Author(s):  
Keqin Gao ◽  
Lianhai Hou
Keyword(s):  
North American ◽  
Upper Cretaceous ◽  
Low Frequency ◽  
Taxonomic Diversity ◽  
Gobi Desert ◽  
Republic Of China ◽  
Terrestrial Vertebrates ◽  
The North ◽  
Central Asian ◽  
Warm Temperate

Squamate fossils collected for the Sino-Canadian dinosaur expeditions (1986–1990) include some 70 specimens from the Upper Cretaceous (Campanian) Djadochta Formation, exposed at the vicinity of Bayan Mandahu, Inner Mongolia, China. Well-preserved skulls, jaws, postcranial skeletons, and even osteodermal armor document a fossil assemblage composed of at least 18 genera in 8 families. Besides showing considerable taxonomic diversity, several families recorded in the assemblage are of importance in understanding the geologic and biogeographic distribution of the relevant groups, and the paleoenvironment in which these lizards lived. Comparison of the Gobi lizard assemblage with North American and Central Asian assemblages is briefly discussed. Taxonomic differences in the assemblage from that of the Upper Cretaceous in the North American Western Interior reflect endemism and suggest a low frequency of interchange of small terrestrial vertebrates between the two regions during Campanian time. The taphonomic setting of the squamate fossils indicates quick burial in arid to semiarid environments in the Gobi Desert, differing importantly from the Western Interior of North America, where the accumulation of disarticulated jaw fragments reflects postmortem decomposition and fluvial transportation under subtropical to warm temperate conditions.

LATE CRETACEOUS EXHUMATION OF UNDERPLATED METASEDIMENTARY ROCKS IN THE NORTH AMERICAN CORDILLERA

2019 ◽  
Author(s):  
William A. Matthews ◽  
◽  
Marie-Pier Boivin ◽  
Kirsten Sauer ◽  
Daniel S. Coutts
Keyword(s):  
Late Cretaceous ◽  
North American ◽  
North American Cordillera ◽  
Metasedimentary Rocks ◽  
The North

scholarly journals Late Turonian-early Coniacian belemnites from western and central Europe

1982 ◽  
Vol 31 ◽  
pp. 63-79
Author(s):  
Walter Kegel Christensen
Keyword(s):  
Central Europe ◽  
Late Cretaceous ◽  
North American ◽  
Evolutionary Trends ◽  
Taxonomic Character ◽  
Central European ◽  
The North ◽  
The Family ◽  
Early Late

A little known fauna of late Turonian--early Coniacian belemnites from the Central European palaeobiogeographic Subprovince is revised and the following species are recognised: Actinocamax strehlensis (Fritsch & Schlonbach), A. bohemicus Stolley, A. paderbornensis Schliiter, and A. esseniensis n. sp. The taxonomic value of various characters within Late Cretaceous belemnites belonging to the family Belemnitellidae Pavlov is discussed, and it is concluded that the shape of the guard is a more significant taxonomic character than the presence of granules. The species from the subprovince are compared to coeval species from the Central Russian Subprovince and the North American Province. The palaeobiogeography and evolutionary trends of early Late Cretaceous belemnites are discussed.

scholarly journals PRELIMINARY REPORT ON THE LACUSTRINE STRATA OF THE SANFRANCISCANA BASIN IN NORTHERN MINAS GERAIS, BRAZIL

2020 ◽  
pp. 1-10
Author(s):  
Jonathas S. Bittencourt ◽  
Pedro L. C. R. Vieira ◽  
Raphael M. Horta ◽  
André G. Vasconcelos ◽  
Natália C. A. Brandão ◽  
...  
Keyword(s):  
Late Cretaceous ◽  
Fossil Record ◽  
Preliminary Report ◽  
Upper Cretaceous ◽  
Minas Gerais ◽  
Fish Scales ◽  
The North ◽  
Younger Age ◽  
First Time ◽  
Pelitic Rocks

We report new data on the geology and the fossil record of the Sanfranciscana Basin in sites to the north of the traditionally explored localities within Minas Gerais. The strata in the new explored area are formed by distinct lithologies, encompassing pelitic rocks with caliche levels and metric bodies of cross-bedded sandstone towards the top, similar to the fluviolacustrine beds of the Areado Group in the southern portions of the basin. Also similar to other regions of the São Francisco Craton, the deposits of the Sanfranciscana Basin studied herein lie discordantly to the rocks of the Bambuí Basin. We preliminarily report neopterygian fish scales, little informative archosaurian bones and an association of the ostracods Ilyocypris- Fossocytheridea. This ostracod association is registered for the first time in the Cretaceous of the Sanfranciscana Basin. The ostracods have been collected from the lacustrine, vertebrate-bearing rocks cropping out in Lagoa dos Patos and Coração de Jesus. The cytherideid Fossocytheridea assigns a minimal Aptian age to its bearing rocks. Its association with Ilyocypris was also reported in Upper Cretaceous oligohaline paleoenvironments in Brazil and Argentina, indicating similar depositional conditions to the strata reported in this paper. The putative affinities of the specimens of the Sanfranciscana Basin with F. ventrotuberculata, and their association with Ilyocypris, raise the hypothesis of a younger age for some levels of that basin in northern Minas Gerais, perhaps ranging into the Late Cretaceous. Keywords: Ostracoda, Archosauria, Areado Group, Cretaceous, Gondwana

A new bird from the Upper Cretaceous Two Medicine Formation of Montana

2002 ◽  
Vol 39 (1) ◽  
pp. 19-26 ◽  
Author(s):  
David J Varricchio
Keyword(s):  
Late Cretaceous ◽  
Upper Cretaceous ◽  
New Genus ◽  
Articular Surface ◽  
Type Specimen ◽  
Depositional Environments ◽  
Western Montana ◽  
New Genus And Species ◽  
Basal Position

A partial humerus, ulna, and radius compose the type specimen of a new bird, Piksi barbarulna, new genus and species, from the Late Cretaceous (Campanian) Two Medicine Formation of western Montana. This ornithothoracine taxon differs from all other birds in having an enlarged dorsal epicondyle and a reduced ventral condyle on the humerus with corresponding modifications on the articular surface of the ulna. Among modern birds, Piksi is most similar to galliforms, but the paucity of unambiguous characters and its unusual morphology defy placement within any extant "order" and strongly questions any neornithine affinities. Instead, Piksi appears to have a fairly basal position within Ornithothoraces. Several morphologic features of Piksi occur in phylogenetically diverse but morphologically similar birds, such as galliforms, tinamous, and some columbiforms. The new bird comes from an inland, relatively dry paleo-environment. Atypical for a Cretaceous avian record dominated by waterfowl, Piksi appears to represents a heavy-bodied ground bird. Searching of inland depositional environments may yield new and ecologically distinct avian varieties.

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