Cretaceous Continental Deposits Research Articles

Grutas del Palacio and other related Upper Cretaceous continental deposits (SW Uruguay): main sedimentary features and evidence for an old flooded forest

Grutas del Palacio and other related Upper Cretaceous continental deposits (SW Uruguay): main sedimentary features and evidence for an old flooded forest

Validation of Dinocarcinus velauciensis Van Bakel, Hyžný, Valentin & Robin, a fossil crab (Crustacea, Decapoda, Brachyura) from Upper Cretaceous (Campanian) continental deposits of Velaux and vicinity, southern France.

Validation of Dinocarcinus velauciensis Van Bakel, Hyžný, Valentin & Robin, a fossil crab (Crustacea, Decapoda, Brachyura) from Upper Cretaceous (Campanian) continental deposits of Velaux and vicinity, southern France.

A new ornithopod dinosaur, Transylvanosaurus platycephalus gen. et sp. nov. (Dinosauria: Ornithischia), from the Upper Cretaceous of the Haţeg Basin, Romania

ABSTRACT Rhabdodontid dinosaurs were a group of medium-sized iguanodontian ornithopods from the Late Cretaceous of Europe. The uppermost Cretaceous continental deposits from the Haţeg Basin of western Romania yielded a very rich assemblage of vertebrates including abundant rhabdodontid remains, which have been exclusively referred to the genus Zalmoxes thus far. Here we describe a new rhabdodontid dinosaur, Transylvanosaurus platycephalus gen. et sp. nov., from the uppermost Cretaceous of the Haţeg Basin. The holotype of the new taxon was discovered in early–late Maastrichtian strata near Pui in the eastern part of the basin and comprises the articulated basicranium and both frontals. Transylvanosaurus differs from all previously reported rhabdodontids in having particularly wide and crested frontals, elongated and straight paroccipital processes that make only a gentle lateral curve and project mostly posterolaterally, prominent and massive prootic processes that extend mainly anterolaterally and ventrally, wide and crest-like basal tubera that meet the long axis of the braincase at a very flat angle, widely splayed basipterygoid processes that extend mainly ventrolaterally and slightly anteriorly, as well as a well-developed notch on the lateral side of the basicranium that is continuous, straight, and inclined anteroventrally. Phylogenetic analyses employing two different datasets consistently recovered the new taxon within the Rhabdodontidae, at the base of the iguanodontian radiation. Based on the morphological comparisons presented herein, we propose a particularly close relationship between Transylvanosaurus and Rhabdodon from southern France, which in turn provides evidence for a more complex biogeographic history of the Rhabdodontidae than previously thought.

Reappraisal of the braincase anatomy of the ornithopod dinosaurs Telmatosaurus and Zalmoxes from the Upper Cretaceous of the Haţeg Basin (Romania) and the taxonomic reassessment of some previously referred specimens

The hadrosauroid Telmatosaurus and the rhabdodontid Zalmoxes were the first and second dinosaur taxa that were described in detail from the famous Upper Cretaceous continental deposits of the Haţeg Basin by Franz Baron Nopcsa at the beginning of the twentieth century. Although they are among the most common and best-known dinosaurs discovered from these deposits, there are still many open questions as to their taxonomy and anatomy. Here, we re-describe two partial braincases from the uppermost Cretaceous of the Haţeg Basin that have been recently referred to the rhabdodontid Zalmoxes and re-assign them to hadrosauroids, possibly to Telmatosaurus. These specimens both exhibit basicranial features that are characteristic of derived hadrosauroids but are absent in more basal iguanodontians. These include an antero-posteriorly short basioccipital lacking a distinct neck, the presence of two well-developed sphenoccipital tubercles on the ventral aspect of the braincase and that are directly positioned anterior to the basioccipital, as well as a deep depression on the ventral aspect of the braincase between the sphenoccipital tubercles. The comparison provided herein demonstrates several important differences between the basicranium of hadrosauroids and that of rhabdodontids, which allows for the confident identification of even isolated and incomplete specimens. Moreover, the removal of the only basicranium that has been referred to Zalmoxes shqiperorum prompts a revised diagnosis of that species.

New data on Barbatodon oardaensis Codrea, Solomon, Venczel & Smith, 2014, the smallest Late Cretaceous multituberculate mammal from Europe

Surprisingly, after the Early Cretaceous taxonomic diversity recorded in Europe, which probably is largely an artifact of inadequate taxonomy and inflation of taxa, multituberculate mammals became extremely scarce in the Late Cretaceous in this continent, being reported exclusively from the uppermost Cretaceous continental deposits of the so-called “Hațeg Island” in Transylvania, Romania. Such mammals have been documented from the Hațeg and Rusca Montană sedimentary basins, as well as from the southwestern area of the Transylvanian Basin. All these records belong to the endemic family Kogaionidae. The present paper reports additional data related to the smallest Cretaceous kogaionid, Barbatodon oardaensis Codrea, Solomon, Venczel & Smith, 2014 based on a series of new isolated teeth recovered mainly from the type locality, Oarda de Jos (Oarda A). Furthermore, the fossil localities Oarda B and Vălioara are other new occurrences for the species. Based on this new material, the intraspecific variability of B. oardaensis is confirmed and its presence is attested in the three basins. Details related to the diversity of the “Hațeg Island” kogaionids are also provided.

Geochemical and palynological records of rapid climatic change from the early to late Aptian: evidence from the Jiaolai Basin, eastern China

The Laiyang Group in the Jiaolai Basin, eastern China, contains Lower Cretaceous continental river and lake deposits that provide a complete record of the evolution of the paleoclimate in the Laiyang area from the early to late Aptian. This study used novel chemical weathering indices and palynological data for Lower Cretaceous mudstone in the Laiyang Group coupled with existing geochemical data, clay mineralogy and plant fossil record to reconstruct the geochemical weathering conditions and paleoclimatic evolution of the Jiaolai Basin over this period. Four distinctive episodes of paleoclimatic change were identified, with one linked to an extremely dry–hot climatic event correlated with the Oceanic Anoxia Event (OAE)1a. During Stage 1, strong chemical weathering was correlated with a relatively warm–humid climate during the early Aptian but the intensity of chemical weathering tended to decrease with an increasingly dry and hot climate. In contrast, Stage 2 was characterised by stable conditions with weak chemical weathering and an extremely dry, hot climate during the early and middle Aptian. The presence of organic-rich black shale and the associated distribution of organic carbon isotope values verified that the extremely dry–hot climate during this stage was related to OAE 1a. Stage 3 was a transitional period extending through the middle and late Aptian during which the climate became relatively warm and humid, triggering increases in chemical weathering. Finally, Stage 4 during the late Aptian was characterised by a return to high chemical weathering rates and a warmer climate. Notably, the paleoclimatic changes in the Aptian period indicated by the geochemical record of the Jiaolai Basin are synchronous with those indicated by marine records. The results of this study provide a reference for further study of this climatic event in terrestrial systems within the context of the greenhouse climate in the Cretaceous. KEY POINTS Geochemical and palynological records of rapid climatic change are preserved in lower to upper Aptian terrestrial sediments in eastern China. Chemical weathering in inland east Asia during OAE 1a first increased, then decreased and then increased again. Terrestrial vegetation responded to global climate change during the early Aptian period in eastern China.

X-ray diffraction studies of onshore mud volcanoes in parts of the Upper Benue Trough, northeastern Nigeria

The mineralogical studies of clay from the onshore mud volcanoes discovered in parts of the Upper Benue Trough of Nigeria provide a clue about the geological formation from which the extruded mud originates. The study area is a part of the Cretaceous Upper Benue Trough filled with Early Cretaceous continental deposits and Late Cretaceous marine deposits, having a history of magmatism dating from the Albian to the Pleistocene. The study approach involves integrated inorganic geochemical analysis of the samples to reveal their composition and origin. The results of XRD analysis of the fresh clays from the mud volcano revealed the presence of quartz, kaolinite, and other clay minerals (illite-smectite), feldspars, and in much lower quantities, other accessory minerals including muscovite, evaporites, calcite and dolomite, trona, barite, goethite. The saprolite samples are composed mainly of quartz, kaolinite, smectite-illite associations, and feldspars, traces of goethite, calcite, and evaporate minerals (sylvite, halite). The presence of calcite, dolomite, sylvite, and halite suggests the marine origin of the rocks, while trona mineral is a non-marine evaporate. The coexistence of these minerals in some of the analyzed samples suggests the deposition of sediments in a transitional environment of deposition. Traces of marine minerals are present in some of the samples but completely absent in others collected from another site. This suggests that the source rock formations from which the material originated are within the Upper Bima Sandstone interpreted as being deposited in a non-marine environment or the Yolde Formation, which is known as a transitional unit (transitional between the outcropping continental Upper Bima Sandstone and marine Pindiga Formation).

A new specimen ofSinopterus dongi(Pterosauria, Tapejaridae) from the Jiufotang Formation (Early Cretaceous, China)

The Tapejarinae are edentulous pterosaurs that are relatively common in Cretaceous continental deposits in South America, North Africa, Europe, and China (mostly Early Cretaceous). The Chinese Jiufotang Formation is particularly rich in tapejarine specimens, having yielded over 10 described specimens and dozens of undescribed ones. For the Jiufotang Formation, a total of seven nominal tapejarid species and two genera have been proposed. Some debate exists over how many of those are valid or, alternatively, sexual or ontogenetic morphs of fewer (or even a single) species. Despite the abundance of specimens and the relevant taxonomic problems involved, detailed revisions of the matter are still lacking. This is partly due to the relatively scarce knowledge on the comparative osteology of the Sinopterus complex, which is hampered by the fact that most specimens have been only preliminarily described. In this contribution, we present a new postcranial specimen, D3072, which we attribute to the type-species of the genus, Sinopterus dongi. This new specimen helps shed some new light in the osteology of Sinopterus dongi, hopefully serving as a basis for future comparative studies involving further specimens and other proposed species and, subsequently, taxonomic revisions.

The uppermost Cretaceous continental deposits at the southern end of Patagonia, the Chorrillo Formation case study (Austral-Magallanes Basin): Sedimentology, fossil content and regional implications

The deposits of the Chorrillo Formation (Maastrichtian) were accumulated during a ‘continental window’ that occurred during the Late Cretaceous in the Austral-Magallanes foreland basin, southern Patagonia, Argentina. The aim of the present contribution is to describe the depositional conditions as well as new vertebrate and plant fossils from this unit. The analysis of these deposits resulted in the definition of five architectural elements: Complex sandy narrow sheets channels (SS), Complex gravelly narrow sheets channels (GS), Sandstone lobes (SL), Thick fine-grained deposits (GF) and Thin dark fine-grained deposits (DF). These were separated into channelized and non-channelized units and represent the accumulation in a fine-grained dominated, fossil rich fluvial depositional system. Vertebrates fossil records include two species of frogs of the genus Calypteocephalella (representing the southernmost record of Pipoidea), snakes belonging to Madtsoiidae and Anilioidea (the latter ones being the first records for the basin), chelid turtles similar to Yaminuechelys-Hydromedusa, meiolaniiform turtles, titanosaur sauropods, megaraptoran theropods, new remains of the elasmarian Isasicursor santacrucensis (including the first cranial remains available for this species), hadrosaur ornithischians, enantiornithine birds. Sharks and elasmosaurs are also recorded and may possibly derive from the overlying marine Calafate Formation. These new taxa, together with previous findings from the Chorrillo Formation, are included into a stratigraphic column, thus providing valuable information that sheds new light on faunistic composition and paleobiogeography of high-latitude biotas of Gondwana.

Dysodiles from the lower Barremian of Lebanon: Insights on the fossil assemblages and the depositional environment reconstruction

The Recent re-/discovery of unusual Lower Cretaceous continental deposits (dysodiles) brings important and exceptional paleontological assets. Dysodile beds are found in many localities across Lebanon and are characterized by their high organic matter content and their richness in exceptionally well-preserved fossils. We focus our study on five sampling localities in the lower Barremian sandstone beds, deposited when Lebanon was located in the north-eastern part of the Gondwana supercontinent. The localities are found associated with volcanic deposits suggesting a close relation between volcanism and their deposition and/or preservation. The present study provides, for the first time, insights on the fossil assemblages found in the dysodiles, including fishes, turtles, gastropods, insects, plant debris (macroflora and palynomorphs), ostracods and coprolites. We provide a preliminary reconstruction of the depositional environment that is common to the five sampling localities. It was a freshwater lake or possibly a series of interconnected lakes, in the vicinity of volcanic edifices, surrounded by a typical Lower Cretaceous flora (open forest environment), and inhabited by basal actinopterygian fishes and teleosts that will constitute the core of subsequent freshwater assemblages. The Lebanon localities have important implications for local palaeoenvironments as well as worldwide biogeography. In addition, the fossil assemblages show some taxonomic and taphonomic differences between the sampling sites, suggesting local differences in environmental conditions during deposition.

Carcharodontosauridae theropod tooth crowns from the Upper Cretaceous (Bauru Basin) of Brazil: A reassessment of isolated elements and its implications to palaeobiogeography of the group

Theropod tooth crowns are abundant in the Upper Cretaceous (post-Coniacian) continental deposits of the Bauru Group, Brazil. The distribution of anatomical crown features indicates that a variety of carnivorous dinosaurs inhabited the area at that time, which is consistent with fossil records from other parts of Gondwana. More specifically, some authors have attributed several isolated specimens to the Carcharodontosauridae; while this has important implications for palaeobiogeography and paleoecology, other scholars have argued that the clade became extinct during the Turonian. In this study, we conducted discriminant and phylogenetic analyses for 18 crowns putatively assigned to the Carcharodontosauridae. In short, the discriminant analysis suggested that the specimens should be tentatively assigned to the following groups: non-abelisauroid Ceratosauria, Abelisauridae, Neovenatoridae, Dromaeosauridae, and Pantyrannosauria. By contrast, the phylogenetic analysis indicated that all should be assigned to abelisaurid theropods, which is consistent with the theropod osteological records in both Brazil and Argentina. We recommend using a combined approach involving morphometric and phylogenetic tools when identifying isolated teeth, as this may yield more reliable identifications. We also suggest that all previous reports on the presence of post-Turonian carcharodontosaurids in the Bauru Group are invalid, which also corroborates previous work. Our results indicate that abelisaurids from the Bauru Basin were diverse in morphology and activity; that is, many were quite large and/or played important ecological roles. Findings also support the hypothesis that this taxon had a preference for semi-arid environments.

Agathoxylon Hartig in the Lower Cretaceous Arroyo del Pajarito Member (Los Adobes Formation), Chubut Province, Argentina

The Cretaceous continental deposits of the Chubut Group are preserved in the Cañadón Asfalto and Golfo de San Jorge basins in Patagonia, Argentina. This unit is known worldwide by the diverse array of tetrapod fauna, including non-avian dinosaurs and other diapsids. Plantremains are somewhat less well known from this unit, in particular in the Cañadón Asfalto Basin region, and only recently several works provided information about foliar impressions and fossil woods. In this contribution, a new report of the ubiquitous genus Agathoxylon is presented from the Arroyo del Pajarito Member of the Los Adobes Formation, representing the second macrofossils described for this formation. Anatomical features allow placing it in Agathoxylon antarcticus (Poole et Cantrill) Pujana, Santillana et Marenssi, 2014, a species found in Mesozoic to Paleogene assemblages from Patagonia and Antarctica. A discussion about the age of the Los Adobes Formation is provided, based on the apparent discordances between palynological and isotopic data.

New ctenochasmatid pterosaur record for Gondwana: discovery in the Lower Cretaceous continental deposits of the Atacama Desert, northern Chile

New pterosaur remains from Cerro La Isla, Quebrada Monardes Formation (Lower Cretaceous), Northern Chile, are described. The material comprises mandibular remains preserving dental bases and two vertebrae of the mid cervical series. The morphology and arrangement of the dental bases show a similar pattern to that observed in European and Chinese ctenochasmatids, but can be distinguished from those other South American ctenochasmatids reported from Argentina and Uruguay. The new vertebrae share certain characteristics with the mid cervical vertebrae of ctenochasmatids, such as very elongated centra with low neural arches, low and elongated neural spines, the presence of postexapophyses and a pair of oval pneumatic foramina on the lateral surfaces of the centra. Although most of these features are shared with the mid cervical vertebrae of azhdarchid pterosaurs, the lower integration of the neural arch, which does not acquire a tubular morphology in the mid-point of the vertebral centrum, together with the presence of oval pneumatic foramina, are characteristics that allow the referral of both vertebrae to the Ctenochasmatidae. The vertebral, mandibular and rostral remains from Cerro La Isla suggest the presence of a previously unknown ctenochasmatid pterosaur, distinct from Pterodaustro, the only other South American taxon.

The oldest freshwater crabs: claws on dinosaur bones

With approximately 1,500 extant species, freshwater crabs (Decapoda: Brachyura) are among the most diverse decapod crustaceans. Nevertheless, their fossil record is extremely limited: only Potamidae, Potamonautidae and Trichodactylidae are reported up to the Eocene of the Neotropics so far. This work documents unusually large decapod claws from the Upper Cretaceous (Campanian) continental deposits of Velaux and vicinity (southern France), in close association with large vertebrate remains. In addition to (1) the systematic assignment of these claws, the study addresses (2) the salinity trends in the deposit environment from its faunal assemblage and the elementary chemical patterns of fossils, and (3) the likely scenario for their auto/allochthony in the Velaux fluvial system. These claws belong to a new taxon, Dinocarcinus velauciensis n. gen. n. sp., referred to as Portunoidea sensu lato, a group of “true” crabs nowadays linked to marine systems. However, the faunal assemblage, the claw taphonomy and the carbonates Y/Ho signatures support their ancient freshwater/terrestrial ecology, making them the oldest reported continental brachyurans and extending the presence of crabs in freshwater environments by 40 Ma. Either as primary or as secondary freshwater crabs, the occurrence of these portunoids in Velaux is an evidence for the independent colonizations of continental environments by multiple brachyuran clades over time, as early as the Campanian.

Taphonomic analysis of saurischian dinosaurs from the Plottier Formation (Upper Cretaceous), Mendoza, Argentina

The uppermost Cretaceous continental deposits of the Neuquén Basin (west-central Argentina) have yielded a high diversity vertebrate assemblage, including numerous dinosaur species. The Neuquén Group is the richest unit in remains of dinosaur of the basin and comprises the Río Limay, the Río Neuquén and the Río Colorado subgroups. In this group, there is abundance of isolated, disarticulated or partially articulated sauropods and theropods. However, little is known about the taphonomic history of fossil assemblages. In this study, dinosaur remains from the Plottier Formation (late Coniacian-early Santonian) found in the Cerro Guillermo area in southern Mendoza are examined. The investigation of fossil occurrences within the study area revealed the existence of different taphonomic modes, from isolated bones until partially articulated skeletons preserved in deposits of floodplain and fluvial channel settings. SEM-EDS analysis showed the substitution of hydroxyapatite by francolite in the bone microstructure. The presence of fluorine-in one of the cases-suggested a link between the elemental composition and depositional environments: floodplain and fluvial channel. The survey of the vertebrate accumulation types and their sedimentary context allowed documenting a wide range of processes responsible for their genesis, operating within a meandering fluvial environment. This contribution represents a holistic approach about taphonomic history of Cretaceous dinosaurs for assessing the differential preservation of fossil assemblages in fluvial environments.

U-Pb detrital zircon constraints on the depositional age and provenance of the dinosaur-bearing Upper Cretaceous Wadi Milk formation of Sudan

Cretaceous continental deposits in Sudan have long been recognized as important archives of continental vertebrate fossils in central Africa. A number of different sedimentary units including the Wadi Milk, Shendi and Kababish formations from northern and central Sudan are known to yield dinosaur and other vertebrate fossils. The ages of these deposits are poorly constrained, and traditionally assumed to be of Albian to Santonian age based on biostratigraphic evidence. However, recent palynological analyses suggest a Campanian–Maastrichtian age for the Shendi Formation. Not only are the ages of these units poorly resolved; but stratigraphic correlations within and between them and similar aged units in central Africa, remains tenuous. To address these issues a detailed sedimentary fingerprinting and provenance analysis was conducted on the putatively correlative Shendi and Wadi Milk formations using sandstone petrography and a multifaceted detrital zircon investigation combining U-Pb geochronology, Lu-Hf isotope analysis and trace element geochemistry. The objective was to provide constraints on the age of deposition, sediment sources and paleofluvial drainage patterns. Based on laser ablation ICP-MS U-Pb detrital zircon geochronology of 18 sandstone samples (>1400 detrital zircons), we identified a population of six Late Cretaceous zircons from the Wadi Milk Formation yielding a maximum depositional age of 79.2 ± 2.4 Ma (MSWD = 0.65, probability 0.62). Specifically, these data restrict the depositional age to Campanian or younger for the Wadi Milk Formation, which significantly refines our understanding of the age of this unit and its fauna. The Lu-Hf-isotope and trace element analyses of the remainder of the dated zircons show a provenance dominated by Neoproterozoic crustal sources and minor Paleoproterozoic and Archean sources for both units, which we interpret as being sourced from the Arabian-Nubian Shield to the south and southeast of the study area. These findings, coupled with the recently updated biostratigraphic age of the Shendi Formation, confirm that both units are correlative to one another and were probably deposited synchronously by north-north westerly flowing fluvial system draining into the Tethys Sea during the Late Cretaceous.

A revision of the holotype of Nanhsiungchelys wuchingensis, Ye, 1966 (Testudines: Cryptodira: Trionychoidae: Nanhsiungchelyidae)

Nanhsiungchelys wuchingensis Ye, 1966 is the type genus and species of the family Nanhsiungchelyidae (Testudines: Cryptodira: Trionychoidae) known from the Cretaceous continental deposits of Asia and North America. The holotype of this species (IVPP V 3106), a partial skeleton from the uppermost Cretaceous of Nanxiong Basin, southern China, represents one of the most complete specimens of that family. Our revision provides new insights on the skeletal morphology. The structure of the forelimb supports a terrestrial mode of life. The phylogenetic relationships are discussed and the more precise stratigraphical information is provided.

Taxonomy of limnic Ostracoda (Crustacea) from the Quiricó Formation, Lower Cretaceous, São Francisco basin, Minas Gerais State, Southeast Brazil

AbstractThe present work presents a detailed taxonomic study on Ostracoda from the Quiricó Formation, Areado Group, São Francisco Basin, Brazil. The samples were collected from three outcrops in the Minas Gerais State: Tereza Farm (João Pinheiro Municipality), and from the banks of the São José and Quiricó creeks (Presidente Olegário Municipality). Sixteen ostracode species were recovered:Harbinia alta,Harbiniaaff.H.angulata,Harbiniaaff. H.crepata,Harbiniaaff.H.salitrensis,Harbinia symmetrica,Brasacypris fulfaroi,Brasacypris ovum,Cypridea conjugata,Cypridea hystrix,Cypridea infima,Cypridea jequiensis,Neuquenocypris(Protoneuquenocypris)antiqua,Penthesilenula martinsi,Penthesilenula pintoinew species,Alicenula longiformisnew species, andTimiriasevia sanfranciscanensisnew species. With the recovery of well-preserved specimens, it was possible to observe new characteristics inBrasacypris ovum,Cypridea conjugata,C.hystrix, andC.infima, and propose emendments to them. Additionally, three new species are described:Penthesilenula pintoin. sp.,Alicenula longiformis, n. sp., andTimiriasevia sanfranciscanensisn. sp. To date, the genusTimiriaseviahad not been recorded in strata from Brazil. Also,Darwinula martinsiis reassigned to the genusPenthesilenula. Several species herein recorded are also found in other Brazilian continental basins, as well as in African and Argentinian basins, contributing to the knowledge of Brazilian Cretaceous continental deposits.

New insights into Europe’s most diverse Late Cretaceous anuran assemblage from the Maastrichtian of western Romania

Uppermost Cretaceous (Maastrichtian) continental deposits in the Transylvanian region of western Romania contain a diverse and important assemblage of fossil vertebrates, including lissamphibians. Bones of anurans (frogs) and albanerpetontids are abundantly represented at multiple vertebrate microfossil localities in the region, but there continues to be no evidence for urodeles (salamanders) at any locality. Using previously reported and new collections of isolated bones, here we provide an up-to-date and comprehensive account of the anuran component of the Romanian assemblage, with particular emphasis on new specimens exhibiting features that are informative for differentiating species and resolving their higher level affinities. We recognise at least five species belonging to two or three families of moderately primitive (i.e. non-neobatrachian), crown-clade anurans: the alytids Paralatonia transylvanica, cf. Bakonybatrachus sp. and cf. Eodiscoglossus sp.; the bombinatorid Hatzegobatrachus grigorescui; and an indeterminate, possible pelobatid. Ilia previously reported as cf. Paradiscoglossus (a monotypic alytid genus reliably known only from the Maastrichtian of western North America) are here referred to Paralatonia. Also present are indeterminate alytids and at least two potentially distinctive, but indeterminate, taxa of uncertain family affinities. New specimens allow Hatzegobatrachus, formerly regarded as incertae sedis, to be assigned to Bombinatoridae as the geologically oldest member of that family. The Romanian Maastrichtian anuran assemblage is the most diverse yet documented for the European Late Cretaceous. It contains a mix of endemic taxa (Paralatonia and Hatzegobatrachus), a relict taxon (cf. Eodiscoglossus sp.), and one taxon (cf. Bakonybatrachus) possibly resulting from a pre-Maastrichtian dispersal from present-day Hungary. Compared to contemporaneous and older (Santonian–Campanian) anuran assemblages elsewhere in Europe, the Romanian assemblage is similar in containing alytids and a pelobatid-like taxon, but differs in having more alytid taxa (n = 3) and a bombinatorid, and in lacking the palaeobatrachids seen in the Campanian–Maastrichtian of Western Europe and the probable ranoid Hungarobatrachus reported from the Santonian of Hungary.

Late Cretaceous (Santonian) Atractosteus (Actinopterygii, Lepisosteidae) remains from Hungary (Iharkút, Bakony Mountains)

Lepisosteid fishes are well known from the Upper Cretaceous of Europe, but only by fragmentary remains from some Cenomanian and Campanian–Maastrichtian deposits. Here we report various cranial and postcranial remains of gars, discovered in the Upper Cretaceous (Santonian) Csehbánya Formation of Iharkút (Bakony Mountains, Hungary). These remains represent one of the most diverse assemblages of lepisosteid fish material from Upper Cretaceous continental deposits of Europe. Based on tooth morphology, scale-microstructure and the features of the supracleithrum we refer these remains to the genus Atractosteus. Besides some uncertain remains from the Cenomanian of France and Spain, the Santonian aged fossils from Iharkút represent the oldest undisputable occurrence of the family Lepisosteidae in the European continental Cretaceous. Using tooth crown morphology, the surface microstructure of the ganoid scales and the anatomy of the supracleithrum a review of the Late Cretaceous lepisosteid record suggests the occurrence of both Atractosteus and Lepisosteus in the European archipelago.