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In the present paper, we provide a comprehensive revision of the large-sized neosuchians Kansajsuchus and ' Turanosuchus ' from the Late Cretaceous of Central Asia. Kansajsuchus extensus from the Kansai locality of the Yalovach Formation, Tadzhikistan, is confirmed as a valid taxon. Previously hypothesized goniopholidid affinities of Kansajsuchus are not supported. Our phylogenetic analyses found this taxon as a derived member of the family-level taxon Paralligatoridae. With a dorsal cranial length of 70–80 cm and a total body length reaching 5–7 m, Kansajsuchus extensus is among the largest known paralligatorids and derived neosuchians in general. The large-sized neosuchian from the Shakh Shakh locality of the Bostobe Formation, Kazakhstan, previously identified as Kansajsuchus spp. ' Turanosuchus aralensis ', or Neosuchia indet. with allegedly goniopholidid affinities, is a paralligatorid closely related to K. extensus. The taxonomic composition, internal relationships and geographical distribution of Paralligatoridae are reconsidered. Paralligatoridae is an endemic clade from the Cretaceous of Asia comprising four recognized genera (Paralligator, Shamosuchus, Rugosuchus and Kansajsuchus), which is characterized by the unique suite of osteodermal features (paravertebral osteoderms with high dorsal keels restricted to posterior margins, arranged in more than two rows and lacking anterolateral processes). [ABSTRACT FROM AUTHOR]

Procoelous caudal vertebrae, a carpometacarpus with a hypertrophied metacarpal II, and robust proximal and ungual phalanges of manual digit II of a small theropod dinosaur from the Upper Cretaceous (Turonian) Bissekty Formation at Dzharakuduk, Uzbekistan, show unequivocal synapomorphies of the clade Alvarezsauridae and thus are referred to it. The caudal vertebrae have a unique longitudinal canal within the neural arch. The carpometacarpus, with metacarpal III occupying about one third of the width of the carpometacarpus, shows the most plesiomorphic stage of the evolution of the forelimb among known alvarezsaurids. The proximal phalanx of manual digit II differs from the corresponding bone in Parvicursorinae in having a less asymmetrical proximal articular surface without a dorsal process and short ventral ridges. The ungual phalanx of manual digit II has laterally open ventral foramina. The Bissekty alvarezsaurid possibly represents a basal parvicursorine and is the stratigraphically oldest known alvarezsaurid in Asia known to date. [ABSTRACT FROM AUTHOR]

The isolated adult teeth of titanosaurian sauropods from the Upper Cretaceous Bissekty Formation at Dzharakuduk, Uzbekistan, differ little in overall structure but show considerable variation in enamel sculpturing and wear patterns. The crown shape of unworn juvenile teeth ranges from lanceolate to conical. Most specimens have enamel texture resembling crumpled paper or completely smooth enamel. Longitudinal grooves along the mesial and distal edges are present on only a few tooth crowns and might be developed on both the labial and lingual sides. Among 252 worn tooth crowns there are eight variants of wear patterns, all possible combinations of 0–2 apical and 0–2 lateral wear facets. The most common is wear pattern A1L0 (one apical facet, no lateral facets; 62.7%). The next most common variant has two apical and no lateral facets (A2L0, 12.3%). These apical wear facets include the primary wear facets, which are produced by an opposing functional tooth, and secondary wear facets, which are produced by a replacing upper tooth coming into contact with the functional lower tooth at a late wear stage. The relative abundance of tooth crowns with two apical wear facets possibly suggests incipient development of a tooth battery in the Bissekty titanosaur. [ABSTRACT FROM PUBLISHER]

Cimolestes Marsh is a North American eutherian mammal primarily known from latest Cretaceous deposits in Alberta, Wyoming, Saskatchewan, and Montana. At present, five species of Cimolestes are considered valid, all Lancian in age; they include one of the largest North American Late Cretaceous therian mammals as well as one of the smallest, a size range far exceeding that within other genera of tribosphenic therians contemporary with Cimolestes, such as the leptictoid eutherian Gypsonictops Simpson or genera of alphadontid or pediomyid marsupials. Moreover, the species of Cimolestes display a disparity of dental morphology in addition to size well in excess of interspecific differences within these genera. Given these considerations, Cimolestes is clearly a grade-taxon, uniting species sharing an adaptively subzalambdodont dentition, but showing divergent specializations within this pattern that are inconsistent with monophyly of its presently included species. To correct these imbalances, this paper limits Cimolestes to Cimolestes incisus Marsh and Cimolestes stirtoni Clemens; Cimolestes magnus Clemens and Russell, Cimolestes cerberoides Lillegraven, and Cimolestes propalaeoryctes Lillegraven are reclassified in the new genera Altacreodus, Ambilestes, and Scollardius, respectively. Altacreodus magnus, having a massive shearing dentition, is reconfirmed as showing a relationship to some Tertiary 'creodonts' not shared by other species of Lancian cimolestids; Ambilestes cerberoides exhibits a distinctive molar wear pattern that emphasized horizontal grinding, not orthal shear; Scollardius propalaeoryctes, the smallest species in this revision and having hyper-faunivorous molars, was not ancestral to Paleogene Palaeoryctidae, as indicated in part by contradictions in premolar number and morphology. [ABSTRACT FROM AUTHOR]

The oviraptorosaurian theropod dinosaur clade Caenagnathidae has long been enigmatic due to the incomplete nature of nearly all described fossils. Here we describe Anzu wyliei gen. et sp. nov., a new taxon of large-bodied caenagnathid based primarily on three well-preserved partial skeletons. The specimens were recovered from the uppermost Cretaceous (upper Maastrichtian) Hell Creek Formation of North and South Dakota, and are therefore among the stratigraphically youngest known oviraptorosaurian remains. Collectively, the fossils include elements from most regions of the skeleton, providing a wealth of information on the osteology and evolutionary relationships of Caenagnathidae. Phylogenetic analysis reaffirms caenagnathid monophyly, and indicates that Anzu is most closely related to Caenagnathus collinsi, a taxon that is definitively known only from a mandible from the Campanian Dinosaur Park Formation of Alberta. The problematic oviraptorosaurs Microvenator and Gigantoraptor are recovered as basal caenagnathids, as has previously been suggested. Anzu and other caenagnathids may have favored well-watered floodplain settings over channel margins, and were probably ecological generalists that fed upon vegetation, small animals, and perhaps eggs. [ABSTRACT FROM AUTHOR]

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Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Upper Cretaceous (Cenomanian-Turonian) formations in the Kyzylkum Desert of Uzbekistan, especially the Bissekty Formation at Dzharakuduk, have yielded a great diversity of continental vertebrates, including dinosaurs. Underwater screening of the sandy matrix has recovered many dinosaurian teeth. Here we describe and illustrate two types of enigmatic theropod teeth that are referable to Paronychodon and Richardoestesia, respectively. Both of these tooth taxa are well known from the Late Cretaceous of North America and possibly represent stages in the development of the teeth of various paravian theropods. Confirmation of this hypothesis awaits discovery of more complete jaws. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: There exists a major gap in the fossil record of tyrannosauroid theropod dinosaurs spanning the early part of the Late Cretaceous. We report on skeletal remains referable to Tyrannosauroidea indet. from the Turonian Bissekty Formation at Dzharakuduk in the central Kyzylkum Desert of Uzbekistan. Phylogenetic analysis of the hypodigm places the Bissekty tyrannosauroid as a non-tyrannosaurid tyrannosauroid more basal than the Campanian tyrannosauroids Appalachiosaurus and Bistahieversor from North America. [Copyright &y& Elsevier]

The osteology of the holotype and referred specimens of the saurolophine hadrosaurid, , from the lower Two Medicine Formation of Montana (USA), is described in detail. With an estimated early Campanian (Late Cretaceous) age, this dinosaur is one of the oldest known hadrosaurids. shows several autapomorphies, including dentary tooth crowns, with an apicobasal length/mesiodistal width ratio of 1.7-2.2, a single median carina, and large marginal denticles in sections of the dental battery; deep and oval depression on the posteroventral premaxillary surface; and, in the context of Hadrosauridae, a shallow lacrimal process of the rostral process of the jugal. Furthermore, differs from and in having a broadly arcuate anterolateral oral margin of the premaxilla, a posterior margin of the narial fenestra that is wider than the dorsoventral depth of the proximal region of the narial bar, with a nasal crest that rises above the level of the frontals (in adults) and is located above the posterior margin of the narial fenestra, and wide and shallow posteroventral margin of the rostral process of the jugal, among other characters. This study confirmed a previous hypothesis supporting as the sister taxon to a clade composed of the other species of . [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since its discovery in 2000, the Iharkút fossil locality in the Upper Cretaceous (Santonian) Csehbánya Formation of western Hungary has yielded a taxonomically diverse assemblage of terrestrial and freshwater vertebrates that continue to provide insights into the diversity, paleobiogeography, and paleoecology of Late Cretaceous vertebrates in Europe. Albanerpetontidae, an extinct group of superficially salamander-like amphibians that were widespread across Laurasia during the latter part of the Mesozoic, are represented at Iharkút by 16 fragmentary jaws. Here we describe and figure these specimens as Albanerpetontidae genus and species indeterminate. Based on the age of the Iharkút locality, several premaxillary features, the known distribution (late Early Cretaceous - late Pliocene) of the type genus Albanerpeton, and an unusually large dentary specimen, we suggest that the Iharkút albanerpetontid may pertain to a previously unrecognized species of Albanerpeton, but verification of that must await the recovery of more diagnostically informative specimens, such as frontals and more nearly complete premaxillae. The Iharkút lissamphibian assemblage contains a mixture of taxa with Laurasian (the albanerpetontid and a discoglossid anuran) and Gondwanan (a neobatrachian anuran) affinities. Intriguing higher level differences are evident among Late Cretaceous Laurasian assemblages; for example, urodeles are scarce or absent (as at Iharkút) in Europe, whereas albanerpetontids are scarce in Middle Asia. [ABSTRACT FROM AUTHOR]