A new carcharodontosaurian theropod dinosaur occupies apex predator niche in the early Late Cretaceous of Uzbekistan

Carcharodontosauria is a group of medium to large-sized predatory theropods, distributed worldwide during the Cretaceous. These theropods were probably the apex predators of Asiamerica in the early Late Cretaceous prior to the ascent of tyrannosaurids, although few Laurasian species are known from this time due to a poor rock record. Here, we describe Ulughbegsaurus uzbekistanensis gen. et sp. nov. from the early Late Cretaceous (Turonian) of Central Asia, which represents the first record of a Late Cretaceous carcharodontosaurian from the region. This new taxon is represented by a large, isolated maxilla from the Bissekty Formation of the Kyzylkum Desert, the Republic of Uzbekistan, a formation yielding a rich and diverse assemblage of dinosaurs and other vertebrates from fragmentary remains. Comparison of the maxilla with that of other allosauroids indicates Ulughbegsaurus was 7.5–8 m in body length and greater than 1000 kg in body mass, suggesting it was the previously unrecognized apex predator of the Bissekty ecosystem while smaller known tryannosauroids and dromaeosaurids were probable mesopredators. The discovery of Ulughbegsaurus records the geologically latest stratigraphic co-occurrence of carcharodontosaurid and tyrannosauroid dinosaurs from Laurasia, and evidence indicates carcharodontosaurians remained the dominant predators relative to tyrannosauroids, at least in Asia, as late as the Turonian.

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An early bothremydid (Testudines, Pleurodira) from the Late Cretaceous (Cenomanian) of Utah, North America

PeerJ ◽

10.7717/peerj.2502 ◽

2016 ◽

Vol 4 ◽

pp. e2502 ◽

Cited By ~ 14

Author(s):

Walter G. Joyce ◽

Tyler R. Lyson ◽

James I. Kirkland

Keyword(s):

Phylogenetic Analysis ◽

Late Cretaceous ◽

New Taxon ◽

The Novel ◽

Depositional Settings ◽

Near Shore ◽

Phylogenetic Hypotheses ◽

North And South America ◽

North And South ◽

Early Late

BackgroundBothremydidae is a clade of extinct pleurodiran turtles known from the Cretaceous to Paleogene of Africa, Europe, India, Madagascar, and North and South America. The group is most diverse during the Late Cretaceous to Paleogene of Africa. Little is known, however, about the early evolution of the group.MethodsWe here figure and describe a fossil turtle from early Late Cretaceous deposits exposed at MacFarlane Mine in Cedar Canyon, southwestern Utah, USA. The sediments associated with the new turtle are utilized to infer its stratigraphic provenience and the depositional settings in which it was deposited. The fossil is compared to previously described fossil pleurodires, integrated into a modified phylogenetic analysis of pelomedusoid turtles, and the biogeography of bothremydid turtles is reassessed. In light of the novel phylogenetic hypotheses, six previously established taxon names are converted to phylogenetically defined clade names to aid communication.ResultsThe new fossil turtle can be inferred with confidence to have originated from a brackish water facies within the late Cenomanian Culver Coal Zone of the Naturita Formation. The fossil can be distinguished from all other previously described pleurodires and is therefore designated as a new taxon,Paiutemys tibertgen. et. sp. nov. Phylogenetic analysis places the new taxon as sister to the EuropeanPolysternon provinciale,Foxemys trabantiandFoxemys mechinorumat the base of Bothremydinae. Biogeographic analysis suggests that bothremydids originated as continental turtles in Gondwana, but that bothremydines adapted to near-shore marine conditions and therefore should be seen as having a circum-Atlantic distribution.

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A new southern Laramidian ankylosaurid, Akainacephalus johnsoni gen. et sp. nov., from the upper Campanian Kaiparowits Formation of southern Utah, USA

PeerJ ◽

10.7717/peerj.5016 ◽

2018 ◽

Vol 6 ◽

pp. e5016 ◽

Cited By ~ 7

Author(s):

Jelle P. Wiersma ◽

Randall B. Irmis

Keyword(s):

Late Cretaceous ◽

First Record ◽

Multiple Time ◽

New Taxon ◽

Postcranial Skeleton ◽

Surface Textures ◽

Close Phylogenetic Relationship ◽

Biogeographic Provinces ◽

Dispersal Events ◽

Upper Campanian

A partial ankylosaurid skeleton from the upper Campanian Kaiparowits Formation of southern Utah is recognized as a new taxon, Akainacephalus johnsoni, gen. et sp. nov. The new taxon documents the first record of an associated ankylosaurid skull and postcranial skeleton from the Kaiparowits Formation. Preserved material includes a complete skull, much of the vertebral column, including a complete tail club, a nearly complete synsacrum, several fore- and hind limb elements, and a suite of postcranial osteoderms, making Akainacephalus johnsoni the most complete ankylosaurid from the Late Cretaceous of southern Laramidia. Arrangement and morphology of cranial ornamentation in Akainacephalus johnsoni is strikingly similar to Nodocephalosaurus kirtlandensis and some Asian ankylosaurids (e.g., Saichania chulsanensis, Pinacosaurus grangeri, and Minotaurasaurus ramachandrani); the cranium is densely ornamented with symmetrically arranged and distinctly raised ossified caputegulae which are predominantly distributed across the dorsal and dorsolateral regions of the nasals, frontals, and orbitals. Cranial caputegulae display smooth surface textures with minor pitting and possess a distinct conical to pyramidal morphology which terminates in a sharp apex. Character analysis suggests a close phylogenetic relationship with N. kirtlandensis, M. ramachandrani, Tarchia teresae, and S. chulsanensis, rather than with Late Cretaceous northern Laramidian ankylosaurids (e.g., Euoplocephalus tutus, Anodontosaurus lambei, and Ankylosaurus magniventris). These new data are consistent with evidence for distinct northern and southern biogeographic provinces in Laramidia during the late Campanian. The addition of this new ankylosaurid taxon from southern Utah enhances our understanding of ankylosaurid diversity and evolutionary relationships. Potential implications for the geographical distribution of Late Cretaceous ankylosaurid dinosaurs throughout the Western Interior suggest multiple time-transgressive biogeographic dispersal events from Asia into Laramidia.

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A new abelisauroid theropod from northwestern Patagonia

Canadian Journal of Earth Sciences ◽

10.1139/e06-025 ◽

2006 ◽

Vol 43 (9) ◽

pp. 1283-1289 ◽

Cited By ~ 16

Author(s):

Rodolfo A Coria ◽

Philip J Currie ◽

Ariana Paulina Carabajal

Keyword(s):

Early Cretaceous ◽

Late Cretaceous ◽

First Record ◽

South American ◽

Middle Section ◽

Theropod Dinosaur ◽

Channel Deposits

The Argentinean record of abelisauroid theropods begins in the Early Cretaceous (Ligabueino) and spans most of the Late Cretaceous, from Cenomanian (Ilokelesia, Xenotarsosaurus, and Ekrixinatosaurus) to Campanian–Maastrichtian (Abelisaurus, Carnotaurus, Aucasaurus, and Noasaurus). A fragmentary specimen of a theropod dinosaur was collected in 2000 from the middle section of the Lisandro Formation (Turonian?) at Cerro Bayo Mesa, Neuquén Province, Argentina. The fossil-bearing level, which is part of the Lisandro Formation that also yielded the remains of the basal ornithopod Anabisetia saldiviai, corresponds to a reddish, massive mudstone linked with fluvial channel deposits. The theropod identified as MCF-PVPH-237 is an abelisauroid theropod that increases our knowledge about the evolution of South American Abelisauroidea and is the first record of this clade from the Lisandro Formation.

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New species of osmundaceous fertile leaves from the upper Triassic of Argentina

Acta Palaeobotanica ◽

10.2478/acpa-2018-0014 ◽

2018 ◽

Vol 58 (2) ◽

pp. 107-119 ◽

Cited By ~ 1

Author(s):

Eliana P. Coturel ◽

Josefina Bodnar ◽

Eduardo M. Morel ◽

Daniel G. Ganuza ◽

Ana J. Sagasti ◽

...

Keyword(s):

New Species ◽

First Record ◽

Late Triassic ◽

Apical Region ◽

New Taxon ◽

Potrerillos Formation ◽

Formed Part ◽

Entire Margin ◽

Early Late ◽

A New Species

AbstractA new species of Osmundopsis Harris is described based on several impression-compression fossils from the upper section of the Potrerillos Formation (Uspallata Group) at Cerro Cacheuta Hill, Mendoza Province, Argentina. Osmundopsis zunigai sp. nov. is characterized by having fertile pinnae with a slender striate rachis, bearing widely separate, opposite to subopposite short falcate pinnules with an entire margin, rounded apex, and a partially reduced lamina. The pinnules bear sporangia loosely disposed in clusters of four or five on the abaxial side. The sporangia are wedge- to heart-shaped, shortly stalked, with cells of the apical region thickened, and have a vertical dehiscence slit. The spores are trilete and laevigate. This is the first record of Osmundopsis in the Triassic of Argentina. The mutual occurrence or co-preservation of Osmundopsis zunigai sp. nov. with sterile fronds of Cladophlebis kurtzi suggests the possibility that these species formed part of a dimorphic bipinnate frond. The diversity and geographic extent of fertile leaves of the Osmunda lineage in the early Late Triassic, with records in South Africa and Antarctica and now with this new taxon, support the idea of a moist mesothermal climatic belt in southern Gondwana.

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Osteology and bone microstructure of new, small theropod dinosaur material from the early Late Cretaceous of Morocco

Gondwana Research ◽

10.1016/j.gr.2014.03.016 ◽

2015 ◽

Vol 27 (3) ◽

pp. 1034-1041 ◽

Cited By ~ 16

Author(s):

David C. Evans ◽

Paul M. Barrett ◽

Kirstin S. Brink ◽

Matthew T. Carrano

Keyword(s):

Late Cretaceous ◽

Bone Microstructure ◽

Theropod Dinosaur ◽

Early Late

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A new basal hadrosaurid (Dinosauria: Ornithischia) from the latest Cretaceous Kita-ama Formation in Japan implies the origin of hadrosaurids

Scientific Reports ◽

10.1038/s41598-021-87719-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yoshitsugu Kobayashi ◽

Ryuji Takasaki ◽

Katsuhiro Kubota ◽

Anthony R. Fiorillo

Keyword(s):

Phylogenetic Analysis ◽

Late Cretaceous ◽

First Record ◽

Early Evolution ◽

Evolutionary Rates ◽

New Taxon ◽

Geographical Distance ◽

Eastern Asia

AbstractHere we describe a partial hadrosaurid skeleton from the marine Maastrichtian Kita-ama Formation in Japan as a new taxon, Yamatosaurus izanagii gen. et sp. nov., based on unique characters in the dentition. Our phylogenetic analysis demonstrates Yamatosaurus izanagii belongs to Hadrosauridae, composed of Hadrosaurus foulkii + (Yamatosaurus izanagii + (Saurolophinae + Lambeosaurinae)). The coracoid lacks a biceps tubercle as in non-hadrosaurid hadrosauroids, suggesting its presence is a key feature for the clade of Saurolophinae and Lambeosaurinae. The evolutionary rates analysis further supports that shoulder and forelimb features, which are likely to have been involved in locomotion, were important for the early evolution of Hadrosauridae. Our biogeographic analyses show that basal hadrosaurids were widely distributed in Asia and Appalachia, that the clade of Saurolophinae and Lambeosaurinae originated in Asia, and that eastern Asia may have served as a refugium of relict hadrosauroid taxa such as Plesiohadros djadokhtaensis, Tanius sinensis, and Yamatosaurus izanagii during the Late Cretaceous. The contemporaneous occurrence of basal (Yamatosaurus izanagii) and derived (Kamuysaurus japonicus) hadrosaurids during the Maastrichtian in Japan is the first record in Asia. Because of the long geographical distance between these localities, they likely did not co-exist, but instead demonstrate some level of provinciality.

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Potentilla × angarensis Popov (Rosaceae Juss.) – a new taxon for the Oka-Don Lowland

Acta Biologica Sibirica ◽

10.3897/abs.7.e62533 ◽

2021 ◽

Vol 7 ◽

pp. 211-218

Author(s):

Alexey A. Kechaykin ◽

Anna B. Bedenko ◽

Vladimir A. Agafonov

Keyword(s):

New Record ◽

First Record ◽

Morphological Characters ◽

European Part ◽

General Distribution ◽

New Taxon ◽

Closely Related Species ◽

Voronezh Region ◽

European Part Of Russia ◽

The Republic

A new locality of the taxon from the genus Potentilla, endemic to the flora of Russia and Kazakhstan, was discovered in Eastern Europe. Previously, P. × angarensis was recorded for the European part of Russia based on collections from Moscow Region and the Republic of Udmurtia. The paper reports the first record of this hybrid for the Oka-Don Lowland, which was found in the northeast of the Voronezh Region. The main morphological characters of the hybridogenic taxon, which distinguish it from closely related species, are listed. The general distribution of P. × angarensis is specified. An image of the herbarium specimen of the new record is presented.

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