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In this paper we report for the first time remains of the long-snouted bony fish ' Protosphyraena ' stebbingi Woodward, 1909 from the Upper Cretaceous of northeastern Italy. The material described herein consists of two rostra, one of which is nearly complete and the other only partially preserved, collected from Crespadoro (Monti Lessini) and Villa di Teolo (Colli Euganei), respectively. The overall morphology and internal structure of the rostrum of ' P.' stebbingi differ from those of the rostra characteristic of the genus Protosphyraena but exhibits a certain degree of similarity to those of some Cretaceous tselfatiiforms. Like in other long-snouted bony fishes, the rostrum of ' P.' stebbingi was probably used for prey capture and defense. The age of the Italian specimens is consistent with that of the English Chalk (Lower Chalk) where the type material of ' Protosphyraena ' stebbingi was collected, especially the specimen from Colli Euganei, which comes from the upper Cenomanian Bonarelli Level. Taphonomic features of the specimens are also discussed, especially those of the rostrum from Crespadoro, which exhibits encrusting calcareous tubes, probably pertaining to deep-sea serpulids. • Description of two rostra of ' Protosphyraena ' stebbingi from Veneto Region (Italy). • Historic background of one of the specimens, belonging to a historic collection. • Discussion of the taxonomic status of ' P. ' stebbingi. • Taphonomic remarks on the specimens here described. [ABSTRACT FROM AUTHOR]

Abstract Cretoxyrhina mantelli was a large pelagic lamniform shark geographically widespread during the Late Cretaceous, and well known because of several nearly complete skeletons from the Western Interior Seaway of North America. Here we report 15 partial skeletons belonging to lamniform sharks from the 'lastame' lithozone of the Upper Cretaceous Scaglia Rossa Formation of the Lessini Mountains (northeastern Italy). Seven partial but articulated skeletons include tooth sets that allow a confident attribution to Cretoxyrhina mantelli based on dental morphologies. We review the taxonomic history of C. mantelli , evidencing that the taxon was erected by Agassiz (1835) and tracing back four of the original syntypes. Based on calcareous plankton biostratigraphy, the rock in which the Italian skeletal remains are embedded is constrained to the middle-upper Turonian. Total length estimates of the specimens suggest that the sample includes the largest specimen of Cretoxyrhina mantelli (615–650 cm estimated total length) known to date. The placoid scale morphology indicates that C. mantelli most likely was a fast swimmer with a similar ecology as the extant white shark, Carcharodon carcharias. The associated skeletal elements of the specimens represent large chondrichthyan deadfalls and the cadavers decayed on the seafloor where they remained exposed for several months, as indicated by bioerosional traces, some of which are interpreted as a product of bone-eating worm activities and other bioerosional traces with Gastrochaenolites -like structure. The Cretoxyrhina mantelli remains described herein provide new information about the ʻlastameʼ vertebrate assemblage, which seemingly was strongly dominated by chondrichthyans, especially lamniform sharks. Highlights • Description of partial skeletal remains of the ʻginsuʼ shark Cretoxyrhina mantelli. • Nomenclatural Remarks about the species C. mantelli. • Emendation of the diagnosis of the species C. mantelli. • Paleobiological and taphonomic Remarks about the deadfalls of C. mantelli. • Micropaleontological analyses on the C. mantelli specimen matrix. [ABSTRACT FROM AUTHOR]

Abstract Dental remains of the elasmobranch Ptychodus from the Upper Cretaceous of northeastern Italy are described herein. This material, consisting of two slabs containing a partially associated tooth set and additional detached teeth with similar morphological features, derives from different lithozones of the Scaglia Rossa Formation, known as the ʻlastameʼ and ʻPietra di Castellavazzoʼ. All of these teeth are characterized by an unusual high and narrow cusp. The tooth set exhibits elements with different morphologies although they are clearly referable to a single taxon. Based on the species-specific characters of the teeth and according to the Principle of Priority of the International Code of Zoological Nomenclature, we propose herein to resurrect the species Ptychodus altior Agassiz, 1835 as a valid taxon that can easily be separated from P. rugosus Dixon, 1850. Moreover, we designate a neotype of Ptychodus altior Agassiz, 1835 since the type series seemingly is lost. Although similarly developed cusps are observed also in the species Ptychodus rugosus Dixon, 1850 and P. whipplei Marcou, 1858, the material described herein is assigned to Ptychodus altior because of the presence of a narrow cusp with smooth lateral cusp faces. The narrow high-cusped morphology characterizing this species probably indicates a different target prey compared to low-crowned congeneric species. Ptychodus altior is solely known from the Turonian-Coniacian of Europe; we review the distribution and paleobiogeography of this species, extending its range to the Angola region. The fossils described herein represent the first record of Ptychodus altior from Italy and significantly contribute to the knowledge of this species and, more generally, of the paleobiodiversity of the genus Ptychodus in the central Tethys area. Highlights • Description of dental remains of high-cusped Ptychodus. • Resurrection of Ptychodus altior Agassiz, 1835 and neotype designation. • Comparison with most similar species, Ptychodus rugosus and P. whipplei. • Discussion of feeding preference and paleobiogeography of Ptychodus altior. [ABSTRACT FROM AUTHOR]

New isolated teeth from the Upper Cretaceous of Ukraine and belonging to the extinct durophagous shark Ptychodus are described here. The taxonomic identification of the examined material reveals a quite diverse Cenomanian shark fauna which comprised both cuspidate and un-cuspidate species of Ptychodus from the coastal areas at the north-western margin of the Ukrainian Massif. In addition, P. latissimus from the Turonian of Ukraine is reported here for the first time. The revision of the Ukrainian record of Ptychodus revealed that most specimens described here are the oldest so far known from this part of the European Peri-Tethys. Moreover, the present study highlights the co-occurrence of cuspidate and un-cuspidate Ptychodus and a variety of shelled macroinvertebrates, which inhabited coastal and offshore areas of the European epicontinental seas during the Late Cretaceous. The availability of different prey items is proposed here as one of the possible drivers, in addition to abiotic environmental factors, for the diversification of shark tooth morphologies, and possible trophic partitioning between cuspidate and un-cuspidate species of the genus Ptychodus. • New isolated teeth of Ptychodus from the Upper Cretaceous of Ukraine. • Diverse fauna of Ptychodus inhabiting coastal seas near the Ukrainian Massif. • Summary of the Cenomanian–Coniacian record of Ptychodus from Ukraine. • Diverse prey fauna as additional driver for tooth diversification in Ptychodus. • Possible niche partitioning between cuspidate and un-cuspidate Ptychodus. [ABSTRACT FROM AUTHOR]

Sclerorhynchiform sawfishes are a diverse and extinct clade of elasmobranchs that is restricted to the Cretaceous. Most taxa are known only by isolated rostral spines, whereas skeletal remains are rare and have been reported from a small number of Upper Cretaceous localities. Here, we describe skeletal remains of the giant sclerorhynchiform Onchosaurus pharao for the first time, which provides new morphological information. The single specimen comes from middle-basal upper Turonian strata of the Lessini Mountains in northeastern Italy and represents the first record of this genus from Italy. The specimen consists of unidentifiable cranial remains, several diagnostic rostral spines, the rostrum with fragments of tessellated calcified cartilage, and 87 disarticulated vertebrae. The rostrum preserves the characteristic sensory system of sclerorhynchiforms. It is devoid of any lateral sockets indicating that rostral spines were attached laterally to its surface. This pattern is identical to most sclerorhynchiforms and extant pristiophoriformes implying also similar replacement patterns as in most other sclerorhynchiforms with the exception for Schizorhiza . Additionally, the bases of two longitudinally arranged rows of ventral rostral spines are identifiable concurring with patterns seen in Sclerorhynchus . The axial skeleton is partly preserved. Re-arranging the disarticulated vertebrae according to their life position in combination with measures of the size and thickness of preserved vertebral centra, and the ratio rostrum length/body size depending on the number of vertebral centra indicate that the specimen was ca. 450 cm long. Growth rings in the vertebral centra show that the specimen was about four years old and thus probably not yet fully sexual mature when it died. This age assumption corresponds well with the calculated size when compared with complete skeletons of extinct sclerorhynchiforms and extant pristiforms. The size of the specimen and its occurrence in hemipelagic rocks corroborates previous assumptions that this sclerorhynchiform was a large and pelagic sawfish. [ABSTRACT FROM AUTHOR]

The lost plant fossil and fish locality of “Monte Colle”, near the village of Bolca, Verona province, northern Italy has been considered to be of Eocene age since the middle of the nineteenth century. However, upon re-examination of the plant fossils, especially the specimens of Aularthrophyton Massalongo, which closely resemble the fossil conifer Frenelopsis Schenk, led us to suspect that a Cretaceous age was more probable. Fieldwork to re-evaluate the local stratigraphy, and the identification of the radiolarians Crucella cachensis Pessagno and Patellula helios (Squinabol) within the matrix of surviving hand specimens, all definitively show that the fossil bed actually belongs to the uppermost Cenomanian Bonarelli Level. With this revised age, we properly describe the gross morphology of the surviving plant specimens and reinterpret their identifications and affinities. Frenelopsis petraepurae comb. nov., Geinitzia sp., and a single angiosperm leaf type are described and the consequences for nomenclature outlined. Comparisons with coeval Cretaceous plant taxa are also discussed. [ABSTRACT FROM AUTHOR]

Fossil plant macroremains were collected from the black shale of the outcrops of the Bonarelli Level near the village of Quero, Venetian Alps, NE Italy. This important radiolarian-ichthyolithic, organic-rich marker bed was deposited close to the Cenomanian/Turonian boundary and represents the sedimentary expression of the global Oceanic Anoxic Event 2 (OAE2). Taphonomic evidence suggests that terrestrial areas were exposed near Quero during the deposition of the black shale assemblage. The floristic assemblage consists of vegetative and reproductive remains belonging to ferns, conifers and angiosperms. Preservation of the material is poor and, therefore, only impressions and compressions have been preserved. In most cases, only gross morphological features were studied. However, cuticular analyses with light and scanning electron microscopy have aided in the description of the new species Frenelopsis veneta. This taxon shares with F. harrisii Doludenko & Reymano´wna and F. kaneviensis Barale & Doludenko the narrow, inter-cell grooves on the outer internodal epidermal surface, but it differs in cuticle thickness, stomatal diameter and stomatal density. An attempt is made to establish relationships between extant families and genera, and the fossil specimens. [Copyright &y& Elsevier]

Dental and skeletal remains of Ptychodus mediterraneus from the Upper Cretaceous Scaglia Rossa Formation of northeastern Italy are described and discussed herein, together with isolated teeth of P. latissimus and P. polygyrus from the English Chalk of Sussex, southern England. The redescription of the holotype of Ptychodus mediterraneus and lectotype fixations for P. latissimus and P. polygyrus allow the systematic reassessment of the three low-crowned Ptychodus species. In addition, these taxa are compared with other morphologically similar species, such as P. martini and P. marginalis. Micropalaeontological analyses suggest a Turonian age for the low-crowned P. mediterraneus. Based on articulated tooth sets of P. mediterraneus , the pavement-like dentitions of this durophagous taxon are reconstructed herein, revealing a marked dignathic heterodonty. Imbricated dentitions observed in articulated specimens of Ptychodus mediterraneus also suggest broad distributions of bite-induced load on tooth plates; the dental features of this low-crowned durophagous shark indicate a high specialization for grinding thick-shelled bivalves (e.g., inoceramids and rudists). Fragments of cranial mineralized cartilages (e.g., a 'V-shaped' jaw portion) of P. mediterraneus are consistent to those commonly occurring in fusiform sharks. Evidences of scavenging on Ptychodus recorded on cartilages and tooth-bioerosion are also reported herein. Moreover, a posterior-to-anterior tooth replacement is hypothesized for Ptychodus based on the abrasion patterns observed in articulated dental sets. New insights on the palaeoecology and palaeobiology of Ptychodus are also provided. • Systematic reassessment of Ptychodus latissimus , P. polygyrus and P. mediterraneus. • Detailed description of the anatomy of P. mediterraneus. • Reconstruction of dental plates of P. mediterraneus based on articulated specimens. • Discussion about feeding specialization, tooth replacement and body morphology. • Taphonomic remarks focused on decay of carcass, scavenging and microborings. [ABSTRACT FROM AUTHOR]

The first articulated dentition of † Ptychodus from Africa is described herein. The specimen, likely coming from the Turonian of the Asfla area (Goulmima region, southeastern Morocco), exhibits a well-preserved lower dental plate of a second-level predator. A new species, † P. maghrebianus sp. nov., is erected herein based on this durophagous dentition characterised by imbricated cuspidate teeth. We employed for the first time in † Ptychodus multiple quantitative analyses and statistical parametric and non-parametric tests to process biometrical data taken from articulated, associated and isolated teeth. The quantitative approach (morphospace analysis) is exploited herein to support the traditional taxonomic identification (qualitative examination) of † P. maghrebianus sp. nov. and to separate it from the similar cuspidate species, † P. mortoni. Morphospace reconstructions confirm a marked lower dental heterodonty (mesio-distal patterns) for both species. The analysis protocol employed here also allows assigning indeterminate teeth as belonging to † P. mortoni. The reconstruction of the entire lower dental plate of † P. maghrebianus sp. nov. shows a cuspidate dentition probably able to reduce tooth damages when crushing thin-shelled prey. Both dental morphologies and tooth wear patterns suggest a peculiar food processing and a diet mainly consisting of bivalves, decapods and small fish for this durophagous predator. Trophic reconstructions of the Turonian ichthyofauna inhabiting the middle to outer ramp environment of the Asfla area emphasize that † P. maghrebianus sp. nov. and the batoid † Tingitanius most likely represented second-level consumers, whereas the sclerorhynchiforms † Asflapristis and † Ptychotrygon represented third-level predators. Top positions within the food web were occupied by larger predaceous elasmobranchs (e.g., † Squalicorax). • Description of the first articulated dentition of † Ptychodus from Africa. • Establishment of the new Moroccan species, † P. maghrebianus. • Identification of cuspidate Ptychodus species based on multiple statistical analyses. • A peculiar food processing hypothesized for the durophagous † P. maghrebianus. • Trophic reconstructions of the Turonian ichthyofauna from the Asfla area (Morocco). [ABSTRACT FROM AUTHOR]

We have carried out an integrated chronostratigraphic analysis of the Alano di Piave section, proposed GSSP for the Bartonian/Priabonian boundary (late Eocene). Age constraints were derived independently from a floating cyclochronology based on carbon isotope and wt.% CaCO 3 records, and 206Pb/238U dating of zircons from four volcanic tuffs. Orbital and radio-isotopic estimates of the duration of intervals bracketed by consecutive crystal-rich volcanic tuff layers are in good overall agreement, but discrepancies of 40–160 kyr are present between nominal volcanic tuff dates derived from astrochronology and 206Pb/238U. The degree to which these discrepancies are statistically significant at the 2 σ level depends on the interpretation of the U-Pb zircon data, and the uncertainties assigned to the astronomical age model. The possible source and significance of these discrepancies are explored in detail. The resulting age model, combined with published bio-, and magnetostratigraphic data, is used to establish the duration of individual magnetochrons in the interval spanning the Bartonian/Priabonian transition, and the timing of late Bartonian-early Priabonian biostratigraphic and magnetostratigraphic events relative to the proposed GSSP, the regionally traceable crystal-rich tuff layer "Tiziano Bed". The chronostratigraphic framework developed at Alano di Piave will facilitate the global correlation of the Priabonian GSSP based on both bio- and magnetostratigraphic criteria. The obtained astrochronology allows a precise correlation of the Alano di Piave δ 13C record with oceanic successions confirming a strong dependency of the marine carbon cycle on astronomical forcing although with inter-site differences, which could be related to water mass organization. • The Alano section (NE Italy) is a suitable candidate for the base of the Priabonian. • U-Pb dating of zircons and cyclochronology provide independent age estimate. • Integrated stratigraphy provides precise calibration of the proposed GSSP. [ABSTRACT FROM AUTHOR]