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Adalatherium hui is a latest Cretaceous (Maastrichtian) gondwanatherian mammal based on only a single specimen, a virtually complete, articulated, and well-preserved skull and postcranial skeleton....

Evolutionary relationships of the endemic South American ungulates (SANUs), both to each other and to other major placental clades, have been robustly debated for more than a century. Morphological...

The fossil record of Early Cretaceous birds in South America has been restricted to members of Enantiornithes from the Crato Formation (Aptian) of Brazil. Here we describe a new genus and species o...

Interatheriinae is one of the most derived subfamilies of South American notoungulates. Several interatheriines have been described since the 19th century, but most of them have not been revised, o...

A new crocodyliform, Sebecus ayrampu, sp. nov., is described based on the rostral region of the skull, mandibular rami, and a distal portion of the femur collected in Paleocene rocks of northwester...

Ornithopod dinosaurs are relatively common in the Cretaceous of Australia, particularly in the state of Victoria, which has yielded five taxa to date: two from the upper Strzelecki Group (upper Bar...

Mosasauroidea sensu Caldwell (2012), inclusive of Aigialosauridae + Mosasauridae, are known from the Cenomanian to the end of the Maastrichtian. Their fossil record is poor and incomplete in the Ce...

We here describe a fossil catfish from freshwater deposits of the Jbel Qatrani Formation of the Fayum Depression, Egypt, as a new species of an extant genus, †Clarotes eocenicus, sp. nov., in the f...

A new hard-shelled sea turtle (Pan-Cheloniidae) with vestigial soft tissues from the lower Eocene (Ypresian) Fur Formation of Denmark is described and illustrated. The fossil (DK 807) comprises a p...

In the case study presented here, we describe a Miocene aetobatid, Aetobatus arcuatus Agassiz, 1843 lower tooth plate that exhibits a longitudinal furrow lesion. Hitherto in the literature, patholo...

Pterosaur fossils from Australia are exceptionally rare. Since the discovery of the continent’s first pterosaur some 40 years ago, fewer than 20 specimens have been described. The Lower Cretaceous ...

A new species of Eusthenodon from the Upper Devonian (Famennian) Catskill Formation was collected from talus blocks at the base of a road cut along the Cogan House Exit Ramp on U.S. 15/Interstate 9...

In the 19th century, natural mummies of amphibians were discovered in the Quercy Phosphorites. The specific collection site was never formally reported, which hampers precise dating of these specimens. Still, the name Bufo servatus was erected based on the external morphology of one of the mummified specimens. A tomography of a similarly preserved specimen revealed a preserved skeleton, soft tissues and gut contents. We analyze here the holotype of Bufo servatus using CT-scanning in order to investigate its potentially preserved internal features. Like the previous specimen, a subcomplete articulated skeleton was identified in the B. servatus holotype. Surprisingly, this skeleton is almost identical to that of Thaumastosaurus gezei, an Eocene anuran from Western Europe to which other specimens from this mummy series were previously assigned. The few differences between the specimen skeletons highlight ontogenetic and intraspecific variations, making T. gezei a junior synonym of B. servatus and creating the new combination Thaumastosaurus servatus. Given its association with previously described Quercy specimens, this redescribed anuran is probably from the same time interval as T. gezei. Previous phylogenetic analyses assigned T. servatus to Ranoides, with natatanuran affinities. Using data from this newly described specimen, we tested here further its taxonomic affinities. Our analyses confirm this position, and formally identify T. servatus as a Natatanuran member of Pyxicephalidae (currently endemic of equatorial Africa) and more precisely, a stem-Pyxicephalinae. This result confirms the origin of Thaumastosaurus, a member of the African herpetofauna occupying Western Europe before the Grande Coupure at the Eocene/Oligocene transition.

Doswellia kaltenbachi is a long-snouted non-archosaur archosauriform known from the Late Triassic of the United States (Virginia and Texas). New material from the Chinle Formation of Arizona repres...

The Early Cretaceous basal neoceratopsian dinosaur Auroraceratops rugosus was described based on a single skull recovered from the Gonpoquan Basin in northwestern Gansu Province, China. The...

The basal neoceratopsian dinosaur Auroraceratops rugosus was described based on a single skull from the Gongpoquan Basin in northwestern Gansu Province, China. The genus is now known from over 80 s...

Basal neoceratopsians are a relatively diverse group of small- to medium-sized herbivorous dinosaurs from the Early to Late Cretaceous of Asia and North America. Although known for over a century, ...

Auroraceratops rugosus from the Lower Cretaceous Zhonggou Formation, Gansu Province, China is characterized by exquisite external preservation of articulated, often ventrolaterally curled remains f...

The species Auroraceratops rugosus was originally described based upon a single skull. With the recovery of over 80 individuals, a complete description of the postcranial skeleton is presen...

Basking sharks are presented in the modern fauna by a single species (Cetorhinus maximus), although they have been much more diverse in the past. This group of sharks first appeared in the fossil record in the middle Eocene of the Antarctic and the U.S.A., but most of the described extinct taxa are known from the Oligocene and lower Miocene of Europe. Gill rakers are the most abundant among basking shark remains and their morphological details play an important role in species diagnostics. The shape of isolated gill rakers from 16 Oligocene localities of Poland was analyzed using various morphological approaches, including geometric morphometrics. Results indicate that descriptive characters have a wide range of variation and low diagnostic value, and they are associated directly with the position of gill rakers on the gill arch. Morphological indices describe proportions by discrete structures and could be effective only in the identification of the stratigraphically most distant taxa. Geometric morphometrics revealed significant differences between all of the species designated earlier except for †Caucasochasma zherikhini and †Keasius parvus. At the same time, considering the obtained results on morphology along with the geographic distance, Oligocene basking sharks from Poland should be assigned to †K. parvus. Geometric morphometrics of gill rakers supports the taxonomic distinctness of both †K. rhenanus and †K. septemtrionalis. Study results indicate that reliable taxonomic attribution of extinct basking sharks by the shape of gill rakers, in the absence of other skeletal elements (teeth and/or vertebrae), should be sample-based using multivariate approaches.

Proterochampsids were a group of stem archosaurs from the Middle–Late Triassic of South America. Using for the first time in proterochampsids quantitative microanatomical and morphological data and an inference model, we analyze the microstructure of postcranial bones of proterochampsids to infer life-history traits dealing with growth dynamics, ontogenetic changes, dermal armor histogenesis and lifestyle. We studied proterochampsid individuals from the Middle–Late Triassic Chanares Formation: three specimens of Chanaresuchus bonapartei: PVL 4575 (osteoderms and femur), CRILAR-Pv 80 (osteoderm) and CRILAR-Pv 81 (humerus), and a femur of a non-identified Rhadinosuchinae specimen (CRILAR-Pv 488). The osteoderms show a compact-uniform composition of parallel-fibered bone and lines of arrested growth (LAGs). The long bones are composed mainly of highly vascularized, parallel-fibered bone and isolated areas of woven-fibered bone in the innermost portion of cortex (only in C. bonapartei PVL 4575). The absence of an external fundamental system (EFS) indicates that all of the sampled individuals were somatically immature at time of death. The absence of mineralized bundles of collagenous fibers supports intramembranous ossification as the developmental origin for the osteoderms. With an inference model used for the first time in proterochampsids, the lifestyle inferred for C. bonapartei is terrestrial. Histological evidence indicates that sexual maturity is reached before both somatic and skeletal maturity. The growth patterns among proterochampsids exhibit some degree of variation even within a single species. Such variation can be due to different causes, including possibly phenotypic plasticity.

The Miocene fossil fish †Pentaceros sakhaliniсus Gretchina, 1975, (Perciformes, Pentacerotidae) is redescribed based on the holotype and numerous additional materials collected on Sakhalin Island (western Pacific, Russian Far East) at the end of the 20th century. The general appearance and body proportions, as well as the presence of multiple (more than three) anal-fin spines, make the Miocene taxon similar to members of the family Pentacerotidae, whereas generalized morphological characters such as the presence of three supraneurals and the absence of rugosity of the superficial head bones differentiate this species greatly from any known pentacerotid genus. Thus, the new genus †Portentosoceros is erected for this fish, which was considered the only known fossil member of the family. Due to the fact that this fish lacks the main synapomorphic characters of the Pentacerotidae, †Portentosoceros gen. nov. is left incertae sedis within the Percoidei, though probably related to Recent armorheads. The observed variability in the number of anal-fin spines (from four to six) in †Portentosoceros sakhalinicus is extremely unusual.

The Middle Triassic was an important time in the evolutionary history of reptiles because it was during this time that many modern groups originated and initially diversified. In this context, the ...

The remains of Late Devonian placoderms from the Holy Cross Mountains area have already been established and widely recognized thanks to the diligent studies of Gorizdro-Kulczycka (1934) and Kulczy...

International audience; The Xenacanthiformes from Central and Eastern European deposits have been extensively studied, but the systematics of the species from the French Carboniferous–Permian Autun Basin (Saône-et-Loire) remains debated. Numerous xenacanthiform remains are still identified under the doubtful genus ‘Expleuracanthus’, and many of them consist of isolated dorsal spines which are difficult to identify. Numerous well-preserved specimens are still undescribed and the diversity of the xenacanthiform fauna from the Autun Basin is poorly understood. For example, specimens of the genus Triodus from the Muse oil-shale bed (OSB) of the Autun Basin have no specific attribution, whereas this genus is widely distributed across European Carboniferous–Permian basins. In this study, we describe new specimens of Triodus from the lowermost Permian of the Muse OSB. They allow the erection of a new species, Triodus aeduorum sp. nov., and discussion of the validity of several species from the same locality: ‘Expleuracanthus’ frossardi is considered as a nomen dubium and other Triodus specimens need for the time being to be left in open nomenclature as Triodus sp. These results highlight the endemism of the Triodus species in each European Carboniferous–Permian basin and raise the question of how they migrated from one to another.

Baenidae are the most diverse clade of turtles from the latest Cretaceous and earliest Paleogene of North America. Palatobaena species have a distinctive cranial bauplan within baenid turtles and we herein describe a new species, P. knellerorum, based on a complete cranium from the lower Paleocene Denver Formation in the Denver Basin, Colorado. Palatobaena knellerorum differs from other Palatobaena species in the extreme degree of its dorsally oriented orbits, as well as the presence of a broad pentagonal midline crest formed by the supraoccipital and parietals. It can be further diagnosed from other species of Palatobaena by the following unique combination of characters: having a broadly rounded cranium, presence of upper temporal emargination that extends well anterior to the otic chamber, a broad exposure of the supraoccipital on the dorsal skull roof, a broadly rounded ‘tongue groove’ between the maxillae and premaxillae, and a deeply emarginated nasal region that exposes the underlying premaxillae in dorsal view. Palatobaena knellerorum most closely resembles the Maastrichtian/Danian taxon Palatobaena cohen and the Danian taxon P. bairdi. A phylogenetic analysis places P. knellerorum as sister to P. bairdi, and these taxa are sister to P. cohen. Palatobaena knellerorum overlaps in time with P. cohen, but the two are separated geographically with P. knellerorum restricted to the Denver Basin and P. cohen restricted to the Williston Basin. Cranial anatomical data and sedimentological data suggest Palatobaena spp. were bottom dwelling turtles living in shallow water environments that used a putative proboscis to prey upon freshwater-shelled invertebrates.

Early chondrichthyans (cartilaginous fishes) possess a rich record of scale fossils that have impacted on taxonomic and phylogenetic studies of early jawed vertebrates, but the significance of these scales remains elusive due to the lack of well-defined characters. Gualepis, a scale-based genus from the Lower Devonian of Yunnan, China, was initially recognized as an early chondrichthyan of uncertain affinity. We investigate new material of Gualepis elegans from the type locality. By combining microtomographic data with morphological and histological examination of specimens at successive growth stages, we have reconstructed the 3D growth pattern of the scales. During growth, Gualepis scales added new odontodes appositionally, which has previously been documented in the dermal skeletons of Seretolepis, Kathemacanthus, Parexus, and other crownward members of the stem chondrichthyans. Phylogenetic analysis resolves Gualepis as a non-acanthodid stem chondrichthyan near the crown chondrichthyan node. Our 3D approach is potentially useful to render more reliable scale-based characters, especially regarding scale growth patterns. This study provides the first 3D virtual growth model of stem chondrichthyan scales with a Seretolepis-type morphogenesis, offering new insights into the early evolution of chondrichthyan dermal skeletons.

The first unequivocal records of teratornithid birds from the Pleistocene of South America are here described, adding a new member, and the largest, to this highly diversified guild of large carnivorous flying birds that lived during these times in the Americas. The new specimens come from four fossiliferous localities of Central Argentina that range in age from the late middle to the early late Pleistocene, and agree with other known Teratornithidae taxa in size and morphology. We updated the taxonomy of the family and analyzed its fossil record in the Pleistocene of both Americas. The available evidence suggests that forms related to Teratornis lived in the South American Pampas around the time of the Last Interglacial (MIS 5), but they were restricted to North America during the latest Pleistocene (late MIS 3–early MIS 1). The contrasting latest Pleistocene record of teratorns between North and South America is not easy to understand, especially because the supposed flight capacity of these birds did not prevent them from crossing large geographical barriers. Although a bias in the fossil record cannot be ruled out, it is possible that the teratorns were limited in South America by paleoclimatic–paleoecological factors as yet undetermined, and/or that the northern and southern Pleistocene species had very dissimilar specializations. In relation to the latter, the previous inferences on the teratorn paleobiology without phylogenetic support are preliminarily questioned here.

Coelacanths are represented today by a single genus, Latimeria. They are known to be ‘living fossils’, because their evolutionary history dates back into the Devonian. Through the Upper Triassic, coelacanths are represented by two families, the Latimeriidae and Mawsoniidae. While latimeriids represent their marine lineage, mawsoniids were, until recently (Deesri et al., 2018), thought to be exclusively freshwater inhabitants. Through the Late Triassic, mawsoniids originated in freshwater environments of America, and only little is known about their evolution in Europe during this time period. Here we report on two morphotypes of mawsoniid basisphenoids from the marine Rhaetian (Upper Triassic) Bonenburg locality (Kreis Hoxter, North Rhine-Westphalia, Germany) showing that (1) Late Triassic coelacanths from Germany can be assigned to the family level, specifically to Mawsoniidae, (2) mawsoniid coelacanths were already present in Europe in the Late Triassic, and (3) these inhabited marine environments at the end of the Triassic, supporting the affinities of habitat preference of previous finds from France (Deesri et al., 2018). The results strengthen the hypothesis an intermediate marine phase between the origin of Mawsoniidae in freshwater environments of nowadays North America during the Late Triassic and their final occurrence in continental deposits of Western Gondwana (Africa and South America) and nowadays Europe in the Late Cretaceous (Cavin et al., 2019).

This paper describes, for the first time, the stapedes of several non-marsupial species of the metatherian clade Sparassodonta (Sipalocyon gracilis, Arctodictis sinclairi, and Borhyaena tuberata) which were fortuitously encountered during routine microtomography. To augment our comparative set we also scanned and reconstructed single examples of the stapedes of the fossil taxa Sparassocynus bahiai and Thylophorops cf. T. chapalmalensis (Didelphimorphia), Argyrolagus scagliai (?Paucituberculata), as well as single examples drawn from extant members of Caenolestidae (Caenolestes sp.) and Microbiotheriidae (Dromiciops gliroides). The sparassodont, didelphid, and microbiotherian samples exhibit a common bauplan (stapes triangular, with intracrural foramen), whereas the paucituberculatan samples differ in possessing columelliform, imperforate stapes as also previously reported for various australidelphians. The stapedial footplate is rounded in sparassodonts (stapedial ratio, ∼1.6), in both of the fossil didelphimorphians (∼1.7), and in the fossil ?paucituberculatan (∼1.5). According to our optimization of our results of mammalian phylogeny, and in contrast to some other reconstructions, a triangular stapes with intracrural foramen and rounded footplate is likely the ancestral condition for Marsupialia. No particular function can be correlated with possession of the intracrural foramen as opposed to an imperforate stapes, apart from accommodation of the proximal stapedial artery (as seen also in many eutherians). The frequent presence of the intracrural foramen in members of both infraclasses suggests that the ontogenies of the second arch's blood supply (stapedial artery) and its main skeletal element (stapes) have remained strongly integrated throughout therian evolution, even in cases in which the proximal part of the vessel involutes.

The Early Carboniferous stem tetrapod Whatcheeria deltae is among the earliest-branching limbed tetrapods represented by multiple near-complete specimens, making it an important taxon in understanding the vertebrate water-to-land transition. However, all preserved skulls of Whatcheeria suffer from post-mortem crushing and lateral compression, which has made cranial reconstruction problematic. In this study, computed tomography data of three Whatcheeria specimens were segmented using visualization software to digitally separate each individual skull bone from matrix. Digital methods were used to repair and retrodeform the bones and produce the first complete three-dimensional skull reconstruction of Whatcheeria. We provide a revised description of the cranial and lower jaw anatomy of Whatcheeria based on CT data, focusing on sutural morphology and previously unknown anatomical details. Our findings suggest that Whatcheeria had one of the narrowest skulls of any known early tetrapod, a gap between the nasals, and significant overlap of the lacrimal onto the nasal and prefrontal. Sutural morphology is used to infer loading regime in the skull during feeding and suggests the skull of Whatcheeria was well adapted to resist stresses induced by biting large prey with its enlarged anterior fangs.

Ornithopods are among the most common members of North America’s Cretaceous dinosaurian faunas, yet despite their excellent representation in existing collections, the anatomy of the manus remains ...

The holotype specimen of Alexandronectes zealandiensis is analyzed using digital reconstruction based on CT scans. Additional information regarding internal anatomy or obscured details are added. Additional features include: ectopterygoid rhombic in shape with posterior end pointed, a feature shared only with Aristonectes quiriquinensis; pterygoid shows a high dorsal crest located anteriorly and laterally to the level of the basipterygoid process; posterior margin of parabasisphenoid medially notched in ventral view and surrounding anteriorly and laterally a midline pit. Two canals for XII nerve are present in the right exoccipital-opisthothic and only one in the left one. Supraoccipital with two medially curved ridges on its posterior surface. Additionally, the presence of a stapes is described for the first time in an aristonectine elasmosaurid. The inner ear labyrinth is described and compared with that of other plesiosaurs, and the floccular recess (osseous correlate of the floccular lobe of the cerebellum) is described for first time among elasmosaurids. This feature is probably related to the presence of a long neck and with predatory behavior as the floccular lobe (housed in the floccular recess) stabilized the head via the cervical musculature, and stabilized the retinal image during rotational head movements.

The phylogenetic relationships of Pseudosuchia, the crocodile-line of Archosauria, are still poorly resolved, in part, due to the lack of crucial braincase information for several key taxa. Recently, erpetosuchids and ornithosuchids have been recovered as close relatives to Aetosauria, sharing several braincase features. Here we provide the description of the first braincase of the basal aetosaur Aetosauroides based on specimens from the Upper Triassic Candelaria Sequence of Brazil. Our study revealed the presence of an exoccipital lateral ridge and a medial ridge on the supraoccipital (both shared with all aetosaurs and erpetosuchids, but absent in ornithosuchids) and an anterolateral exit for the internal carotids (shared with all aetosaurs and ornithosuchids, but not with erpetosuchids). Aetosauroides lacks a medial contact between the exoccipitals (shared with the aetosaurs Desmatosuchus smalli and Tecovasuchus) and possesses a single hypoglossal foramen (contrasting with Stagonolepis robertsoni and Desmatosuchus spurensis). It also differs from the putative Argentinian Aetosauroides (PVSJ 326) by the presence of a ridge connecting the basal tubera medially (contrasting also with all stagonolepidoideans) and by a bulbous and ventrolaterally recurved basipterygoid process (contrasting with Paratypothorax). These features show that the braincase of aetosaurs is suitable for providing further phylogenetic information and may contribute to resolving controversies within Pseudosuchia relationships.

A partial skull (BP/1/7976) of a very large cynodont from the Middle Triassic Cynognathus Assemblage Zone (Cricodon-Ufudocyclops subzone) of South Africa is described. The specimen represents a new...

Sabertooth craniodental adaptations have evolved numerous times amongst carnivorous mammals. Some of the most extreme sabertooth adaptations are found within the carnivoran subfamily Barbourofelina...

Theropod dinosaurs are minor components of Late Triassic ecosystems in North America, comprising coelophysoids and various non-neotheropods from the Chinle Formation of Arizona, Utah, Colorado, and...

Fil: Fernandez, Marta S.. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Division Paleontologia Vertebrados; Argentina

Permian dicynodonts were discovered in strata exposed on the flanks of the Bogda Mountains (Xinjiang, China) in 1928. Nearly all known specimens were collected in the Guodikeng Formation (= upper W...

Trematosaurids were globally distributed Early Triassic temnospondyl amphibians characterized by elongate ‘crocodile-like’ skulls. Some of the most famous trematosaurid fossils were discovered on t...

Metoposaurids are some of the most commonly occurring tetrapods in non-marine Upper Triassic sediments in the northern hemisphere of Pangea. Since the first description of a metoposaurid in 1842, n...

During their long evolutionary history crocodylomorphs achieved a great diversity of body sizes, ecomorphotypes and inferred feeding ecologies. One unique group of crocodylomorphs are the thalattosuchians, which lived during the Jurassic and Cretaceous (ca. 191–125 Ma). They transitioned from shallow marine species, like teleosauroids, into fully pelagic forms with paddle shaped limbs and a vertically orientated tail fluke, the metriorhynchids. The osteological adaptations that allowed metriorhynchids to live in the water are generally well understood, but less is known about their neurosensory and endocranial systems, such as the brain, inner ears, sinuses and cranial nerves and how they relate to their aquatic lifestyle. Based on micro-computed tomography (μCT) data and three-dimensional models, we here describe the braincase and endocranial anatomy of a fully marine metriorhynchid, ‘Metriorhynchus’ cf. ‘M.’ brachyrhynchus (NHMUK PV OR 32617). We found several neuroanatomical features that likely helped this species function in its marine environment. These include a unique flexure in the brain endocast not seen in other thalattosuchians. Other features that have previously been seen in thalattosuchians include enlarged cerebral hemispheres, a hypertrophied venous sinus system, enlarged internal carotid arteries and foramina, and closed/absent lateral pharyngotympanic foramina. The specimen also possesses a pelagic metriorhynchid bony labyrinth morphology, with a compact and dorsoventrally short shape, thick semicircular canals, an enlarged vestibule and potentially a short cochlear duct. A review of character distribution confirms that some of these features evolved at the base of Thalattosuchia in semiaquatic species, long before metriorhynchids became pelagic, suggesting that endocranial anatomy helped allow metriorhynchoids colonize the ocean realm.

The fossil record of temnospondyl amphibians in the immediate wake of the Permo-Triassic mass extinction captures extensive taxic and ecological diversity, with most records known from high paleola...

Tanius sinensis was one of the first dinosaur species to be named from China. It was established on a partial skeleton recovered by a joint Sino-Swedish expedition in 1923. The fossils were excavated from Upper Cretaceous strata of the Jiangjunding Formation (Wangshi Group) in Shandong Province, and although their discovery dates back almost 100 years, they have not been reassessed in detail since their initial description in 1929. This omission is critical because T. sinensis is now recognized as one of the stratigraphically youngest non-hadrosaurid hadrosauroid taxa. Here, we re-evaluate the postcranial osteology of T. sinensis as a prelude to an anatomical and phylogenetic revision of the species. We examined the holotype and all currently referred specimens of T. sinensis first-hand, and identified a unique postcranial character state combination incorporating tall dorsal neural spines, a reduced postacetabular ridge on the ilium, a fully enclosed flexor tunnel formed by the distal condyles of the femur, and a lunate proximal end on metatarsal III. Comparisons with other species of Tanius confirm that: (1) T. chingkankouensis is a nomen dubium erected on non-diagnostic composite material; (2) T. laiyangensis was established on indeterminate hadrosaurid remains that are not attributable to Tanius; and (3) the anecdotal assignments of Bactrosaurus prynadai and Tsintaosaurus spinorhinus to Tanius cannot be substantiated. Close inspection of the holotype caudal vertebra further reveals a possible healed bite trace consistent with a prey-predator interaction. Lastly, our calculated average body mass estimate for T. sinensis of between 2091-3533 kg suggests that it was one of the largest non-hadrosaurid hadrosauroids.

Panzhousaurus rotundirostris Jiang, Lin, Rieppel, Motani and Sun, 2019, is restudied on the basis of a second specimen from the Upper Member of the Guanling Formation near Panzhou City, Guizhou Pro...

The middle and late Eocene perissodactyl fossil record of western Iberia is characterized by an endemic fauna, which is clearly different from those of northeastern Iberia and other areas of the Eu...

Here, we report new dental remains of a large giraffid from the Late Miocene of Pakistan. The new material improves our knowledge of the dental morphology of this extinct sivatherine giraffid, as i...

Throughout the evolutionary history of Avialae, several members of this clade have evolved into giant forms, in different time periods and ecological contexts. In Europe, the first birds that show ...

Recently collected temnospondyl fossils from the Cisuralian Pedra de Fogo Formation (north-eastern Brazil) indicate a diverse assemblage of aquatic tetrapods, including the dvinosaurs Timonya annea...

During the recovery from the end-Permian extinctions in the Middle Triassic, small reptiles (