PALEONTOLOGY IN NOVEMBER, 2024
PALEONTOLOGY IN NOVEMBER, 2024
Embedded Files
Sauropterygian remains from the Middle Triassic of Araif El-Naqa as the first identification of Simosauridae (Eosauropterygia) in Egypt -11/30/24
ABSTRACT
Simosauridae is a Triassic eosauropterygian clade restricted to the western Paleotethys. It is known by relatively abundant cranial and postcranial elements coming mostly from European localities, where the type species, Simosaurus gaillardoti, from the Ladinian (Middle Triassic) of France and Germany, and the recently defined Paludidraco multidentatus, from the Carnian (Late Triassic) of Spain are known, in addition to several simosaurids of undetermined generic and specific attribution. By contrast, it is poorly represented in the Middle East, being known from both Israel and Saudi Arabia by scarce remains of uncertain systematic attribution. The Middle Triassic deposits of Araif El-Naqa, in Egypt, have yielded several sauropterygian remains, so far attributable to the placodont taxa Psephosauriscus sinaiticus and Psephosauriscus rhombifer, as well as to indeterminate nothosaurs. Here, we describe several unpublished vertebral sauropterygian remains from Araif El-Naqa, identifying the presence of the clade Simosauridae for the first time in Egypt and the first simosaurid vertebral remains from the Eastern Mediterranean.
LINK(S)
https://www.sciencedirect.com/science/article/pii/S0016699524001013
The internal braincase anatomy of Thalattosuchus superciliosus – with implications for the endocranial evolution of metriorhynchid crocodylomorphs -11/29/24
ABSTRACT
Thalattosuchian crocodylomorphs underwent a major evolutionary transition, evolving from semiaquatic forms reminiscent of extant crocodylians, into pelagic marine forms with flippers, a tail fin and smooth scaleless skin. These fully aquatic forms – the Metriorhynchidae – evolved a novel suite of endocranial anatomies hypothesised to be related to living in saltwater. However, much remains to be discovered about the evolution of these internal braincase structures. Herein, we describe the endocranial anatomy of an early diverging metriorhynchid, Thalattosuchus superciliosus, using microfocus computed tomography (μCT) data and three-dimensional modelling. We compared it against geosaurine and metriorhynchine metriorhynchids, as well as the early diverging metriorhynchoid Pelagosaurus. We found that non-geosaurine metriorhynchids differ from geosaurines in having less laterally expanded cerebral hemispheres, shallower curvatures of the brain’s dorsal margin, and lacking the ventral deflection of the pneumatic diverticulum ventral to the pituitary fossa chamber. However, early-diverging metriorhynchids have well-defined otoccipital diverticula and lacked the ‘extreme pelagic’ endosseous labyrinth morphology. We hypothesise that early metriorhynchids were not adapted to a sustained pursuit lifestyle. Moreover, we posit that within both metriorhynchid subfamilies there was parallel evolution towards becoming pursuit predators.
LINK(S)
https://www.tandfonline.com/doi/full/10.1080/08912963.2024.2427096
https://www.tandfonline.com/doi/pdf/10.1080/08912963.2024.2427096?needAccess=true
The first record of Lamniformes sharks from the Late Cretaceous in Abu Tartur area, Egypt -11/29/24
ABSTRACT
The outcrops of the Duwi Formation (Late Campanian in age) in the Maghrabi-Liffiya sector of the Abu-Tartur Plateau have produced numerous chondrichthyan teeth. Forty-nine isolated teeth represent two different species: Scapanorhynchus rapax and Cretoxyrhina mantelli. The majority of the teeth were found within a yellow phosphate bed and with the rest contained within the black phosphate bed. The teeth were collected mainly through surface sampling. The Duwi Formation marks the onset of fully marine conditions in Egypt coinciding with the region’s major marine transgression during the Late Cretaceous. This paper reports the first description of Lamniformes from the southwestern desert of Egypt and records the youngest discovery of Cretoxyrhina mantelli in Africa and the Middle East and perhaps the youngest worldwide.
LINK(S)
https://www.tandfonline.com/doi/full/10.1080/08912963.2024.2432905
Evaluation of the paleoecology of Megaraptora (Dinosauria: Theropoda) using biomechanical approaches -11/28/24
ABSTRACT
Megaraptor theropods represent an enigmatic and unusual lineage of dinosaurs that are characterized by their unique bauplan that includes a low, elongated skull and robust forelimbs with enlarged claws. Such unusual morphology has led to speculation that these theropods primarily used forelimbs rather than jaws to capture or feed on prey. However, in-depth biomechanical studies of the functions of their claws or jaws are scarce. In this work, jaw force profiles of the Australian megaraptor Australovenator wintonensis are analyzed using the principle of beam theory, and the mechanical advantages of the first ungual phalanges of several megaraptor taxa. Mandibular force profiles reveal that the lower jaw of Australovenator wintonensis behaved as a simple lever, suitable for performing cutting bites and probably incapable of producing a high bite force. Biomechanical modeling of early megaraptor ungual phalanges suggests a decline in mechanical advantage in more derived taxa, indicating that claws became more adapted to hook and pull function during the course of evolution in this clade. Such results imply that megaraptors such as Australovenator wintonensis fed mainly on relatively small animals, or relied more on their forelimbs to hunt large prey by hooking their claws on the victim and pulling them, tearing or cutting the flesh.
LINK(S)
https://turia.uv.es/index.php/sjpalaeontology/article/view/29797
Tahnaichthys magnuserrata gen. and sp. nov., a double-hump pycnodontid (Actinopterygii, Pycnodontiformes) fish from the Albian limestones of the Tlayúa Quarry, Puebla, Mexico. -11/27/24
ABSTRACT
Tahnaichthys magnuserrata gen. and sp. nov. is described here based on three well-preserved Albian specimens recovered in the lagoon-coastal deposits of the Tlayúa Quarry, Puebla, Mexico. This species belongs to the order Pycnodontiformes and shows the diagnostic features of the family Pycnodontidae, including the presence of a posterior parietal process distally branched, toothless reniform maxilla, anterior thin wings at the base of the haemal and neural spines, and slender dentary with two teeth. In addition, this species shows unique features never observed before in other pycnodontids as the presence of two unequal predorsal humps or prominences, including a slight hump just behind the occiput and a large hump rising in front of the dorsal fin. The predorsal scutes are thick, have a longitudinal row of unequal spines, and show thin lateral wings projected ventrally, covering a large part of the predorsal trunk region. In the new species, the modified bar-like scales of the predorsal region have tiny posterior wings ornamented with tubercles scattered or arranged in dorsoventral short ridges. In addition, the premaxilla of this new species is ventrally broad and has a large single incisiform tooth opposing two small, oval dentary teeth. This new species exhibits a peculiar mixture of osteological features that, for the moment, complicate its taxonomic designation at the suprageneric level (subfamily or tribe). Although this is the second pycnodontiform species from Tlayúa formally described, the present discovery increases the taxonomic diversity of the pycnodontids in North America and the Paleogulf of Mexico domain.
LINK(S)
https://www.sciencedirect.com/science/article/abs/pii/S0895981124004991
Early-diverging plesiosaurs from the Pliensbachian (Lower Jurassic) of northwestern Germany -11/26/24
ABSTRACT
The knowledge of Pliensbachian (Early Jurassic, ∼192.9–184.2 Ma) plesiosaurs is notoriously insufficient. Although there have been specimens described from different parts of the world, only three of them have been established as diagnosable taxa. Here, we describe two previously unreported lower Pliensbachian plesiosaur occurrences that originate from two sites located in North Rhine-Westphalia, Germany. One of the new occurrences is represented by three cervical and three indeterminable vertebrae from Werther, the other includes two associated pectoral or anterior dorsal vertebrae from Bielefeld. Although highly incomplete, the Werther individual, which derived from the Uptonia jamesoni Zone, is found to represent the only reliably identified early Pliensbachian pliosaurid known to date. Its material is geographically and stratigraphically proximate to the late Pliensbachian pliosaurid Arminisaurus schuberti, found in a clay-pit located in the Bielefeld district of Jöllenbeck. However, even though the Werther plesiosaur and A. schuberti show a broadly similar morphology of the preserved cervical section, a precise identification of the Werther taxon is currently impossible.
LINK(S)
Immature Daspletosaurus sp. specimens from the Dinosaur Park Formation provide insight into ontogenetically invariant tyrannosaurid cranial morphology -11/26/24
ABSTRACT
Understanding the extent to which tyrannosaurid cranial morphology changed through ontogeny is essential to correctly refer tyrannosaurid specimens at varying life stages to taxa. However, taxonomically diagnostic immature tyrannosaurid bones remain exceedingly elusive. Over the last century, the University of Alberta has collected three isolated immature cranial bones referable to Daspletosaurus from Dinosaur Provincial Park, Alberta of Treaty 7 Territory. These bones were all collected from the rocks of the Dinosaur Park Formation and include a premaxilla (UALVP 48717), jugal (UALVP 61561), and lacrimal (UALVP 47955). To assess the taxonomic utility of these bones, they were compared to tyrannosaurid material from the Dinosaur Park and Oldman Formations of Alberta. This provided an opportunity to examine size-independent discrete characters in tyrannosaurid crania. The results of this study suggest that many premaxillary, jugal, and lacrimal discrete characteristics observed in Daspletosaurus are constrained throughout ontogeny. A single ontogenetically invariant character, the dorsal flange of the palatal process, was identified for Daspletosaurus premaxillae. Ontogenetically invariant characters of the jugal include, but are not limited to, a medial lacrimal slot and the lateral fossa on the postorbital process. Invariant lacrimal characters include an anteroposteriorly short pneumatic recess opening and a subdivided nasal articulation fossa on the medial surface of the bone. The identification of these characters allows specimens of the tyrannosaurine Daspletosaurus and the contemporaneous albertosaurine Gorgosaurus to be confidently identified regardless of ontogenetic stage. These characters were applied to a controversial tyrannosaurid specimen from the Dinosaur Park Formation, TMP 1994.143.0001, resulting in referral to Gorgosaurus libratus, rather than Daspletosaurus sp.
LINK(S)
https://cdnsciencepub.com/doi/abs/10.1139/cjes-2024-0083?journalCode=cjes
The Extinct Shark Genus Cretodus (Lamniformes: Pseudoscapanorhynchidae) from the Uppermost Part of the Upper Cretaceous Fairport Chalk in Kansas, USA, and Its Stratigraphic and Ecological Significance -11/25/24
ABSTRACT
Cretodus is an extinct lamniform shark genus that is known from the Albian–Santonian marine deposits nearly worldwide with three recognized categories: the longiplicatus/emiplicatus-grade, the gigantea/houghtonorum-grade, and the crassidens-grade Cretodus. FHSM VP-19857 is a Cretodus tooth housed in the Sternberg Museum of Natural History in Kansas, USA. It occurred from the upper part of the Fairport Chalk Member (mid-Middle Turonian) of the Carlile Shale in Hamilton County, Kansas. This specimen is significant because it represents the geologically latest occurrence of the longiplicatus/semiplicatus-grade Cretodus in Kansas and further supports the hypothesis that Cretodus (at least members of the longiplicatus/semiplicatus- and gigantea/houghtonorum-grades) preferred nearshore environments.
LINK(S)
Unenlagiid affinities for Imperobator antarcticus (Paraves: Theropoda): Palaeobiogeographical Implications -11/23/24
ABSTRACT
Imperobator antarcticus is a paravian dinosaur based on fossil remains of the left and right hind limbs from the Cape Lamb Member (lower Maastrichtian) of the Snow Hill Island Formation, Antarctica. The only known specimen includes the tibia, astragalus, calcaneum, fragments of metatarsals, and non-ungual and ungual phalanges. It was originally described as a paravian with uncertain affinities, as it exhibits a mosaic of characters, such as the fusion of the calcaneum and fibula, a non-ginglymoid metatarsal II, and the absence of hyper-specialization of pedal digit II, forming the raptorial digit typical of deinonychosaurian dinosaurs. Previous authors indicate that it may be related to dromaeosaurids and unenlagiids. Imperobator was included in the TWiG data matrix to recognize its phylogenetic affinities. This comprehensive dataset was further improved by re-scoring and reanalysis of most unenlagiids. Additionally, 11 new taxa (including Imperobator and South American paravians like Pamparaptor and Overoraptor) were added, resulting in a data matrix of 175 taxa and 850 characters. The STAR 1 methodology proposed by previous authors was followed to construct phylogenetic trees. As a result, Imperobator antarcticus is nested within the Unenlagiidae clade. Despite its incomplete nature, Imperobator exhibits a subarctometatarsalian pes, a condition regarded as a Unenlagiidae synapomorphy by the present analysis. In dromaeosaurids, such as eudromaeosaurians and halszkaraptorines, metatarsal III is not lateromedially compressed, shows subparallel medial and lateral margins, and is not constricted between metatarsals II and IV. Imperobator antarcticus constitutes an important addition to the list of Late Cretaceous dinosaurs shared by South America and Antarctica.
LINK(S)
https://www.ameghiniana.org.ar/index.php/ameghiniana/libraryFiles/downloadPublic/120
A new and large monofenestratan reveals the evolutionary transition to the pterodactyloid pterosaurs -11/18/24
ABSTRACT
For over a century, there was a major gap in our understanding of the evolution of the flying Mesozoic reptiles, the pterosaurs, with a major morphological gap between the early forms and the derived pterodactyloids. Recent discoveries have found a cluster of intermediate forms that have the head and neck of the pterodactyloids but the body of the early grade, yet this still leaves fundamental gaps between these intermediates and both earlier and more derived pterosaurs. Here, we describe a new and large Jurassic pterosaur, Skiphosoura bavarica gen. et sp. nov., preserved in three dimensions, that helps bridge the gap between current intermediate pterosaurs and the pterodactyloids. A new phylogeny shows that there is a general progression of key characteristics of increasing head size, increasing length of neck and wing metacarpal, modification to the fifth toe that supports the rear wing membrane, and gradual reduction in tail length and complexity from earlier pterosaurs into the first pterodactyloids. This also shows a clear evolution of the increasing terrestrial competence of derived pterosaurs. Furthermore, this closes gaps between the intermediates and their ancestors and descendants, and it firmly marks the rhamphorhynchines and ctenochasmatid clades as, respectively, being the closest earliest and latest groups to this succession of transitional forms.
LINK(S)
https://www.cell.com/current-biology/fulltext/S0960-9822(24)01377-0
https://www.cell.com/action/showPdf?pii=S0960-9822%2824%2901377-0
Reassessment of an azhdarchid pterosaur specimen from the Mifune Group, Upper Cretaceous of Japan -11/16/24
ABSTRACT
The Japanese pterosaur record is relatively scarce and represented by a limited number of fragmentary specimens from Cretaceous deposits, including a partial cervical vertebra of an azhdarchid from the “Upper Formation” (Turonian-Coniacian) of the Mifune Group in Kumamoto Prefecture, on the island of Kyushu, Japan. Here, we redescribe this notable Japanese pterosaur specimen and test its phylogenetic position. We interpret it as a sixth cervical vertebra and identify diagnostic features that enable its recognition as a new taxon, Nipponopterus mifunensis gen. et sp. nov. It is noteworthy that this represents the first nominal species of pterosaur from Japan and that this new taxon shows numerous quetzalcoatline features, being strikingly similar to the unnamed Burkhant azhdarchid from the Turonian–Coniacian of Mongolia. Our phylogenetic analysis places Nipponopterus as a sister taxon to the Burkhant azhdarchid and nested within the clade of Quetzalcoatlinae.
LINK(S)
https://www.sciencedirect.com/science/article/abs/pii/S0195667124002192?via%3Dihub
Mummy of a juvenile sabre-toothed cat Homotherium latidens from the Upper Pleistocene of Siberia -11/14/24
ABSTRACT
The frozen mummy of the large felid cub was found in the Upper Pleistocene permafrost on the Badyarikha River (Indigirka River basin) in the northeast of Yakutia, Russia. The study of the specimen appearance showed its significant differences from a modern lion cub of similar age (three weeks) in the unusual shape of the muzzle with a large mouth opening and small ears, the very massive neck region, the elongated forelimbs, and the dark coat color. Tomographic analysis of the mummy skull revealed the features characteristic of Machairodontinae and of the genus Homotherium. For the first time in the history of paleontology, the appearance of an extinct mammal that has no analogues in the modern fauna has been studied.
LINK(S)
A new moradisaurine captorhinid reptile (Amniota: Eureptilia) from the upper Permian of India -11/14/24
ABSTRACT
Upper Permian rocks of the former supercontinent Gondwana record climax late Paleozoic terrestrial vertebrate faunas that were dominated numerically and ecologically by therapsid synapsids. Older faunal elements of earlier Paleozoic faunas, such as captorhinid reptiles, are rare and scattered components of the first amniote faunas to inhabit high-latitude regions. Here we describe a new genus and species of moradisaurine captorhinid that represents an archaic faunal element of the high-fibre herbivore fauna of the late Permian of what is now peninsular India. The presence of a relatively broad parietal and three rows of conical teeth on the maxilla and the dentary distinguishes Indosauriscus kuttyi gen. et sp. nov. from other moradisaurines. The hypodigm of I. kuttyi comprises skulls that range in length from 39 mm to 54 mm, and high ossification of the braincase elements and well developed skull-roof sutures, indicate that I. kuttyi adults were smaller than those of most moradisaurines. Results of our phylogenetic analyses suggest that moradisaurines, despite appearing first in the paleotropics, dispersed into temperate, high-latitude regions of Pangea early in their evolutionary history. Moradisaurines in dicynodont-dominated faunas, viz. Indosauriscus kuttyi and Gansurhinus naobaogouensis, were the smallest high-fibre herbivores in their respective faunas. This suggests that small body size may have evolved in these moradisaurines as they co-evolved with the more numerous and diverse dicynodont therapsids.
LINK(S)
First discovery of Antarctic amber -11/12/24
ABSTRACT
Here, we report the first discovery of Antarctic fossil resin (commonly referred to as amber) within a ~5 cm-thick lignite layer, which constitutes the top part of a ~3 m-long palynomorph-rich and root-bearing carbonaceous mudstone of mid-Cretaceous age (Klages et al. 2020). The sedimentary sequence (Fig. 1) was recovered by the MARUM-MeBo70 seafloor drill rig at Site PS104_20 (73.57° S, 107.09° W; 946 m water depth) from the mid-shelf section of Pine Island trough in the Amundsen Sea Embayment, West Antarctica, during RV Polarstern Expedition PS104 in early 2017 (Gohl 2017; Fig. 1a). So far, amber deposits have been described from every continent except Antarctica (Langenheim 2003, Quinney et al. 2015; Fig. 1a).
LINK(S)
A new ankylosaurid dinosaur from the Upper Cretaceous of Jiangxi Province, southern China -11/8/24
ABSTRACT
Huaxiazhoulong shouwen gen. et sp. nov. is a new ankylosaurid recovered from the Upper Cretaceous Tangbian Formation of Jiangxi Province, southern China. Huaxiazhoulong shouwen can be diagnosed on the basis of three autapomorphies (the middle shaft and distal end of the ischium are expanded; the ratio of width of distal end to minimum shaft width is greater than 3 in humerus, the maximum length of femur to humerus length ratio is about 1.45) and a unique combination of characters (the centra of anterior caudal vertebrae in anterior view is heart-shaped; the dorsal surface of scapula is straight; the scapulocoracoid has a large medial brace; the humeral head and deltopectoral crest are separated by a distinct notch anteriorly). The phylogenetic analysis shows that Huaxiazhoulong shouwen is an early member of Ankylosauridae.
LINK(S)
https://www.tandfonline.com/doi/full/10.1080/08912963.2024.2417208
New evidence for the presence of carcharodontosaurid theropod dinosaurs in the Late Cretaceous of Uzbekistan -11/6/24
ABSTRACT
An incomplete posterior dorsal vertebra ZIN PH 2646/16 from the Upper Cretaceous (Turonian) Bissekty Formation of Uzbekistan has a highly pneumatized centrum and neural arch. The centrum has a lateral pneumatic foramen that is divided by a septum. The neural arch is invaded through a lateral pneumatic foramen above the neurocentral suture and has deeply excavated prezygapophyseal-centrodiapophyseal and centrodiapophyseal fossae. The interior of the preserved portion of the neural spine is pneumatic. In the structure of the fossae on the neural arch and the presence of a double pneumatic foramen on the centrum, ZIN PH 2646/16 closely resembles the carcharodontosaurid Acrocanthosaurus from the Early Cretaceous of North America. Thus, we identify ZIN PH 2646/16 as Carcharodontosauridae indet. Carcharodontosauridae were previously known from the Bissekty Formation from Ulughbegsaurus uzbekistanensis, which is based on an incomplete maxilla.
LINK(S)
https://www.tandfonline.com/doi/full/10.1080/08912963.2024.2423675
Gigantopithecus fossils discovered in the Early Pleistocene strata in Wulong, Chongqing -11/3/24
ABSTRACT
The fossil materials studied in this paper, dominated by well-preserved isolated cheek teeth, were unearthed from a horizontal limestone cave named the Meiziwan Cave (29°25′22″N, 107°30′42″E, elevation 589 m asl) in Baima Town of Wulong District, Chongqing Municipality, China. Three premolars (right P4, right p3 and left p4) and six molars (two left M3s, two left m1, left m2 and right m3) were interpreted as Gigantopithecus blacki . Measurements and comparison indicate that giant ape specimens from the Meiziwan Cave are characterized by small sizes and high proportion of dental caries and with adult and old adult to be the majority, representing the primitive form of G. blacki . The deposits in the cave are mainly calcareous clay mixed with karst breccias, bearing abundant mammalian tooth fossils. The faunal association, consisting of at least six orders, fourteen families, seventeen generations, and eighteen species, coincides with those found in the Longgopo site in Wushan County, Chongqing Municipality, the Gigantopithecus cave in Liucheng County and the Baikong Cave in Chongzuo City and the Chuifeng Cave in Bubing basin, Guangxi Zhuang Autonomous Region (Guangxi ZAR) as well as the Pa'eryan Cave in Bijie City, Guizhou Province in light of the special components of the initial stage of the Early Pleistocene, for example, small-sized G. blacki , Hystrix magna , Sinomastodon yangziensis , Stegodon huananensis , Ailuropoda microta , Ursus thibetanus primitinus , Equus cf. yunnanensis , Hesperotherium sinense, Tapirus sanyuanensi s, Sus xiaozhu , S. peii and Cervavitus ultimus. G. blacki become larger through time from the Early Pleistocene to the Middle Pleistocene due to the comparison of tooth measurements. In addition to G. blacki , increase of body size can be found in giant panda, tapir and black bear. Considering occurred in the Mid-Pleistocene climate transition, the tendency can be thought to be bound up with prominent climate transition and ecosystem changes, corresponding to the hypothesis of the Bergman's Rule that endothermy animals grow larger as the climate cools. The Meiziwan Cave is one more G. blacki locality in Chongqing, situated within the area between the Longgupo site in Wushan, Chongqing and the Pa'eryan Cave in Bijie, Guizhou. The presence of G. blacki in the Meiziwan Cave enriches the localities found near the upper and middle reaches of the Yangtze River and broadens the biogeographic distribution ranges, highlighting the significance of the evolution, extinction, paleogeographic distributions, and paleoecosystem of the Gigantopithecus fauna. Fortunately, given the abundance of karst pits, fissures and caves in the area from 30° to 18° latitudes in southern China, further investigations, excavations and research will potentially contribute to figuring it out.
LINK(S)
https://www.anthropol.ac.cn/CN/10.16359/j.1000-3193/AAS.2024.0057
https://www.anthropol.ac.cn/article/2024/1000-3193/1000-3193-43-05-701.shtml
A gigantic new terror bird (Cariamiformes, Phorusrhacidae) from Middle Miocene tropical environments of La Venta in northern South America -11/3/24
ABSTRACT
Our knowledge of the fossil avifauna from the Middle Miocene La Venta locality in Colombia is limited almost entirely to aquatic birds. Phorusrhacidae, popularly known as ‘terror birds’, are a group of highly diversified cursorial birds that played the role of apex predators during most of the Cenozoic. Here we present the first record of a phorusrhacid from the La Venta locality. This terror bird can be assigned to the ‘Phorusrhacinae’, a subfamily for which the monophyly is under debate. The fragment of left distal tibiotarsus represents the most northern record of this group for South America and may correspond to the largest terror bird that ever existed. This suggests that terror birds might also have inhabited more tropical ecosystems, providing evidence that they were apex predators in tropical palaeocommunities. Additionally, our research contributes to an understanding of the biogeographical patterns of the Phorusrhacidae lineage dispersal into northern South America and subsequent colonization of North America.
LINK(S)
Looks like you've reached the end, check back later for new updates
JOIN US ON SOCIAL MEDIA:
Page updated
Google Sites
Report abuse