scholarly journals Yakemys multiporcata n. g. n. sp., a Large Macrobaenid Turtle from the Basal Cretaceous of Thailand, with a Review of the Turtle Fauna from the Phu Kradung Formation and Its Stratigraphical Implications

Diversity ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 630
Author(s):  
Haiyan Tong ◽  
Phornphen Chanthasit ◽  
Wilailuck Naksri ◽  
Pitaksit Ditbanjong ◽  
Suravech Suteethorn ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Carapace Length ◽  
New Taxon ◽  
Shell Elements

Yakemys multiporcata n. g. n. sp. is described on the basis of shell elements from the upper part of the Phu Kradung Formation (basal Cretaceous), Khorat Plateau, NE Thailand and assigned to Macrobaenidae. The new taxon is unusually large for an early macrobaenid (with an estimated carapace length about 70 cm) and is characterized by a large, rounded, low shell, the presence of a midline keel and numerous additional strong ridges on the carapace, the anterolateral margin upturned to form a gutter, posterolateral peripherals mesiolaterally expanded, narrow vertebrals, the vertebral 4 triangular and narrowed posteriorly, a greatly reduced plastron with a short bridge, an oval and elongate entoplastron with reduced ventral exposure, and strip-shaped epiplastra. The discovery of a macrobaenid turtle provides further support for an Early Cretaceous age for the upper part of the Phu Kradung Formation.

A new taxon of birds (Aves) from the Early Cretaceous of Western Siberia, Russia

2011 ◽  
Vol 9 (1) ◽  
pp. 109-117 ◽  
Author(s):  
Evgeny N. Kurochkin ◽  
Nikita V. Zelenkov ◽  
Alexandr O. Averianov ◽  
Sergei V. Leshchinskiy
Keyword(s):  
Early Cretaceous ◽  
Western Siberia ◽  
New Taxon

scholarly journals A new baenid turtle from the early Paleocene (Torrejonian) of New Mexico and a species-level phylogenetic analysis of Baenidae

2016 ◽  
Vol 90 (2) ◽  
pp. 305-316 ◽  
Author(s):  
Tyler R. Lyson ◽  
Walter G. Joyce ◽  
Spencer G. Lucas ◽  
Robert M. Sullivan
Keyword(s):  
Phylogenetic Analysis ◽  
New Mexico ◽  
Carapace Length ◽  
Distal Phalanx ◽  
Species Level ◽  
New Taxon ◽  
Large Size ◽  
Early Paleocene ◽  
A New Species ◽  
Level Analysis

AbstractNew cranial and postcranial material of the baenid turtleNeurankylusfrom the Paleocene Nacimiento Formation (Torrejonian NALMA) of northwestern New Mexico represents a new species,Neurankylus torrejonensis. The material consists of a fragmented but mostly complete skull, a partial carapace and plastron, portions of both humeri, a partial pelvis, a complete right femur, and a distal phalanx. The small, undivided cervical scale, wide vertebrals, complete ring of marginals, and large size (carapace length 520 mm) diagnose the new taxon as belonging toNeurankylus. The narrow fifth vertebral scale and scalloped posterior shell margin reveal affinities withNeurankylus baueriGilmore, 1916, which is known from Campanian sediments in New Mexico and Utah. The holotype ofNeurankylus torrejonensisis the youngest known specimen of theNeurankyluslineage, which is known to reach at least back to the Late Cretaceous (Santonian). A nearly complete species-level analysis of baenids confirms the basal placement ofNeurankylusoutside of Baenodda and the split of Baenodda into two primary subclades, herein named Palatobaeninae and Eubaeninae.

scholarly journals Redescription of Arundel formation Ornithomimosaur material and a reinterpretation of Nedcolbertia justinhofmanni as an “Ostrich Dinosaur”: Biogeographic implications

2016 ◽  
Author(s):  
Chase Doran Brownstein
Keyword(s):  
United States ◽  
North America ◽  
Early Cretaceous ◽  
Fossil Record ◽  
East Coast ◽  
The United States ◽  
Eastern North America ◽  
New Taxon ◽  
Western North America ◽  
The Past

The fossil record of dinosaurs from the Early Cretaceous of eastern North America is scant, and only a few sediments to the east of the continent are fossiliferous. Among them is the Arundel Formation of the east coast of the United States, which has produced among the best dinosaur faunas known from the Early Cretaceous of eastern North America. The diverse dinosaur fauna of this formation has been thoroughly discussed previously, but few of the dinosaur species originally described from the Arundel are still regarded as valid genera. Much of the Arundel material is in need of review and redescription. Among the fossils of dinosaurs from this formation are those referred to ornithomimosaurs. Here, I redescribe ornithomimosaur remains from the Arundel Formation which may warrant the naming of a new taxon of dinosaur. These remains provide key information on the theropods of the Early Cretaceous of Eastern North America. The description of the Arundel material herein along with recent discoveries of basal ornithomimosaurs in the past 15 years has allowed for comparisons with the coelurosaur Nedcolbertia justinhofmanni, suggesting the latter animal was a basal ornithomimosaurian dinosaur rather than a “generalized” coelurosaur. Comparisons between the Arundel ornithomimosaur and similar southeast Asian ornithomimosaurian material as well as ornithomimosaur remains from western North America suggest that a lineage of ornithomimosaurs with a metatarsal condition intermediate between that of basal and derived ornithomimosaurs was present through southeast Asia into North America, in turn suggesting that such animals coexisted with genera having a more primitive metatarsal morphology as seen in N. justinhofmanni.

scholarly journals A unique exceptionally well-preserved pterosaur skull from the Crato Formation of Brazil

2017 ◽  
Author(s):  
Hebert Bruno Nascimento Campos ◽  
Aude Cincotta ◽  
Eberhard Frey ◽  
Pascoal Godefroit ◽  
Johan Yans
Keyword(s):  
Early Cretaceous ◽  
Soft Tissues ◽  
Posterior Part ◽  
Northeastern Brazil ◽  
New Taxon ◽  
Exceptional Preservation ◽  
New Information ◽  
Specific Morphology ◽  
Parallel Fibres ◽  
Sagittal Crest

The posterior part of a skull from a tapejarid pterosaur was studied for the exceptional preservation of its soft-tissues. The specimen comes from the Early Cretaceous (Aptian) Crato Formation of northeastern Brazil. It shows a peculiar soft sagittal crest that gives new information about the anatomy and the diversity of tapejarids. The specimen lies on five limestone slabs. The bony part comprised the posterior part of the skull, with the braincase and one complex of three dorsally oriented and associated bony crests. The crest consists of a huge and elongated parietal crest, a trabecular frontal crest, and an occipital spine. The specimen preserves the posterior parts of the nasoantorbital fenestra and orbit. The soft cranial crest is characterized by a multilinear dorsal crest with almost parallel fibres, which curve posteriorly. Pigment organelles – melanosomes – were observed in the crest as well as ‘hair-like’ fibres (pycnofibres). They present diverse shapes and sizes, suggesting diverse colorations for the soft tissues. The new tapejarid shares certain features with the tapejarids Tupandactylus imperator and “Huaxiapterus” benxiensis, which include an elongated parieto-occipital crest. Nonetheless, it differs from Tupandactylus imperator and Ingridia navigans by the following characteristics: absence of a suprapremaxillary spine, very dorsally oriented posterior crests, as well as a specific morphology for the soft crest. Our specimen can therefore be assigned to a new taxon of Tapejaridae, a group previously reported from the Crato Formation.

scholarly journals New semionotiform (Neopterygii) from the Tlayúa Quarry (Early Cretaceous, Albian), Mexico

Zootaxa ◽  
2011 ◽  
Vol 2749 (1) ◽  
pp. 1 ◽  
Author(s):  
ADRIANA LÓPEZ-ARBARELLO ◽  
JESÚS ALVARADO-ORTEGA
Keyword(s):  
North America ◽  
Early Cretaceous ◽  
Early Jurassic ◽  
Central Mexico ◽  
New Taxon ◽  
Ventral Border

We describe a new semionotiform fish, Tlayuamichin itztli gen. et sp. nov. from the Early Cretaceous (Albian) of Mexico, which constitutes one of the youngest semionotid articulated remains. The new taxon is represented by five well-preserved specimens from the Tlayúa Quarry near Tepexi de Rodríguez in Puebla State, central Mexico. A series of paraethmoid bones anterior to the supraorbital series, supraorbital bones extending beyond the anterior rim of the orbit, the presence of a large pentagonal supraorbital closing the anterior rim of the orbit, seven anterior infraorbitals, dorsally expanded infraorbitals at the ventral border of the orbit, and the most dorsal suborbital separating the preoperculum from the dermopterotic are potential autapomorphic features of the new taxon. The very long frontals, a dermopterotic that does not contact the anterodorsal corner of the operculum and the presence of a modified pectoral scale are additional features that help to diagnose the taxon. Tlayuamichin itztli gen. et sp. nov. resembles most closely “Lepidotes” minor from the Middle Purbeck Beds (early Berriasian), England. These two taxa share similarity with other species of Semionotus from the Early Jurassic of North America and the Triassic of Europe, suggesting interesting biogeographic relationships.

scholarly journals Reinterpretation of a previously described Jehol bird clarifies early trophic evolution in the Ornithuromorpha

2018 ◽  
Vol 285 (1871) ◽  
pp. 20172494 ◽  
Author(s):  
Xiaoting Zheng ◽  
Jingmai K. O'Connor ◽  
Xiaoli Wang ◽  
Yan Wang ◽  
Zhonghe Zhou
Keyword(s):  
New Species ◽  
Early Cretaceous ◽  
Tooth Loss ◽  
Direct Evidence ◽  
New Taxon ◽  
Gastric Mill ◽  
Ecological Inference ◽  
Close Inspection ◽  
Apparent Loss ◽  
A New Species

STM35-3 from the Yixian Formation is the only Early Cretaceous ornithuromorph preserving direct evidence of granivory. The crop contains numerous seeds and the preservation of gastroliths presumably within the ventriculus indicates this diet was paired with the presence of a gastric mill as in living granivorous birds. STM35-3 was originally referred to Hongshanornis longicresta , member of a diverse clade of small, basal ornithuromorphs with elongate hindlimbs known as the Hongshanornithidae. Hindlimb proportions suggest that hongshanornithids were wading birds, an ecological inference somewhat in conflict with direct evidence suggesting Hongshanornis fed on seeds. However, close inspection of STM35-3 reveals that the specimen represents a new species not closely related to hongshanornithids, distinguished by large forelimbs that exceed the length of the hindlimbs, robust and narrow coracoids, and a delicate edentulous rostrum. By contrast, all hongshanornithids have hindlimbs that far exceed the length of the forelimbs, coracoids with wide sternal margins, and small teeth throughout the upper and lower jaws. Reinterpretation of this new taxon, Eogranivora edentulata gen. et sp. nov, helps to clarify trophic driven patterns of tooth loss within the Ornithuromorpha. Apparent loss of the hallux may represent the first such occurrence in a Mesozoic bird and suggests a highly terrestrial lifestyle.

The affinities of a new theropod from the Alxa Desert, Inner Mongolia, People's Republic of China

1993 ◽  
Vol 30 (10) ◽  
pp. 2107-2127 ◽  
Author(s):  
Dale A. Russell ◽  
Zhi-Ming Dong
Keyword(s):  
Early Cretaceous ◽  
Inner Mongolia ◽  
Junior Synonym ◽  
People’S Republic Of China ◽  
New Taxon ◽  
People's Republic Of China ◽  
Republic Of China ◽  
Short Tail ◽  
Skeletal Reconstruction

Remains of bipedal saurischians from lacustrine strata of Albian age in the Alxa ("Alashan") Desert of Inner Mongolia represent a new taxon and the most complete remains of an Early Cretaceous theropod so far discovered in Asia. A skeletal reconstruction generally resembles that of a moderately large prosauropod with long arms and a short tail. However, in its detailed morphology the reptile appears to be close to the ancestry of the Therizinosauridae Maleev, 1954 (for which Segno-sauridae Perle, 1979 is probably a junior synonym). These theropods are best referred to the Tetanurae of Gauthier, 1986. However, a provisional analysis of the distribution of therizinosauroid characters within tetanurans suggests the existence of two subordinate groups: the Carnosauria (Allosaurus, dromaeosaurids, and tyrannosaurids) and the Oviraptorosauria (including therizinosauroids, ornithomimids, troodontids, and oviraptorids).

A new side-necked turtle (Pleurodira, Pelomedusoides) from the Santana Formation (Early Cretaceous), Araripe Basin, Northeastern Brazil

Zootaxa ◽  
2007 ◽  
Vol 1425 (1) ◽  
pp. 53-61 ◽  
Author(s):  
GUSTAVO RIBEIRO DE OLIVEIRA ◽  
ALEXANDER WILHELM ARMIN KELLNER
Keyword(s):  
Early Cretaceous ◽  
New Genus ◽  
Neural Plate ◽  
The Other ◽  
Northeastern Brazil ◽  
New Taxon ◽  
New Genus And Species ◽  
Santana Formation

The fossil fauna of turtles from the Santana Formation, Araripe Basin, Early Cretaceous from Northeastern Brazil, includes, to exception of the Santanachelys gaffneyi (Cryptodira, Protostegidae), only pelurodiran taxa. A new genus and species, Caririemys violetae gen. et sp. nov. (Pleurodira, Pelomedusoides), from the Romualdo Member, upper section of the Santana Formation, is described here. Caririemys is based on one specimen consisting of a carapace, several vertebrae, a right femur and a right pelvis. Caririemys differs of the other pleurodirans from the Santana Formation by the following combination of characters: oval and moderately domed carapace; complete neural series reaching the suprapygal; and neural plate 8 shows an extensive contact with costal 7 and 8. This new taxon enhances the turtle diversity of the Santana Formation, which is presently the most diverse deposit of Mesozoic Testudines in the country.

scholarly journals A derived dryolestid mammal indicates possible insular endemism in the Late Jurassic of Germany

2021 ◽  
Vol 108 (3) ◽  
Author(s):  
Thomas Martin ◽  
Alexander O. Averianov ◽  
Julia A. Schultz ◽  
Achim H. Schwermann ◽  
Oliver Wings
Keyword(s):  
Phylogenetic Analysis ◽  
Early Cretaceous ◽  
Lower Cretaceous ◽  
Middle Jurassic ◽  
Late Jurassic ◽  
New Taxon ◽  
Lower Saxony ◽  
Therian Mammal ◽  
Geological Age ◽  
Near Shore

AbstractThe Langenberg Quarry near Bad Harzburg has yielded the first Jurassic stem therian mammal of Germany, recovered from Kimmeridgian (Late Jurassic) near shore deposits of a palaeo-island within the Lower Saxony Basin of the European archipelago. The new stem therian is represented by one lower and three upper molars. Hercynodon germanicus gen. et sp. nov. is attributed to the Dryolestidae, a group of pretribosphenic crown mammals that was common in western Laurasia from the Middle Jurassic to the Early Cretaceous. The new taxon is characterised by small size, a reduced cusp pattern in the upper molars lacking a metacone, and enhancement of the shearing crests paracrista and metacrista. Phylogenetic analysis identified Hercynodon gen. nov. as sister taxon of Crusafontia from the Lower Cretaceous (Barremian) of Spain. Both taxa belong to an endemic European clade of dryolestids, including also Achyrodon and Phascolestes from the earliest Cretaceous (Berriasian) of England. Despite its greater geological age, Hercynodon gen. nov. is the most derived representative of that clade, indicated by the complete reduction of the metacone. The discrepancy between derived morphology and geological age may be explained by an increased rate of character evolution in insular isolation. Other insular phenomena have earlier been observed in vertebrates from the Langenberg Quarry, such as dwarfism in the small sauropod Europasaurus, and possible gigantism in the morganucodontan mammaliaform Storchodon and the pinheirodontid multituberculate mammal Teutonodon which grew unusually large.

scholarly journals A New Early Cretaceous lizard in Myanmar Amber with Exceptionally Preserved Integument

2021 ◽  
Author(s):  
Andrej Čerňanský ◽  
Edward L. Stanley ◽  
Juan D. Daza ◽  
Arnau Bolet ◽  
J. Salvador Arias ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Morphological Analysis ◽  
Sister Taxon ◽  
Phylogenetic Position ◽  
Pectoral Girdle ◽  
New Taxon ◽  
Anterior Portion ◽  
External Appearance ◽  
Rare Opportunity ◽  
Rule Out

Abstract We here report on a well-preserved juvenile lizard specimen in Albian amber (ca. 110 mya) from the Hkamti site in Myanmar. This new taxon, Retinosaurus hkamtiensis gen. et sp. nov., is represented by an articulated skull and the anterior portion of the trunk, including the pectoral girdle and forelimbs. The ocular skeleton (scleral ossicles) and eyelid are also visible, and the specimen exhibits pristine detail of the integument (of both head and body). In a combined molecular and morphological analysis, Retinosaurus was consistently recovered as a scincoid lizard (i.e. Scinciformata), as the sister taxon to the Mexican Cretaceous genus Tepexisaurus + Xantusiidae. However, the phylogenetic position of Retinosaurus should be interpreted with caution. We cannot not rule out the possibility that Retinosaurus represents a separate lineage of uncertain phylogenetic position, as it is the case for many Jurassic and Cretaceous taxa. Nonetheless, this fossil offers a rare opportunity to glimpse the external appearance of one group of lizards during the Early Cretaceous.

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