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Elasmobranch faunas of the Molasse (Paratethys, Miocene, Oligocene)
With the present first part of the study the ray species from the Molasse of Baltringen (Baden-Wuerttemberg, SW Germany) published by Probst (1877) are reinterpreted and taxonomically updated to the current state of knowledge. The main focus of this work is on the illustration originals or types deposited in the museum of the Eberhard Karls University of Tuebingen. The material was verified regarding completeness, inventoried and examined in detail. 32 types as well as 10 illustration originals could be found; 13 used or newly introduced species names were evaluated as nomina dubia, one species and one illustration original is a tooth or rostral spine of a shark (Raja grandis = Ginglymostoma delfortriei Daimeries, 1889; Pristis sp. = Pristiophorus suevicus Jaekel, 1890). Keywords: Batoidea, Miocene, Ottnangian, North Alpine Foreland Basin, Molasse.
The deposit is located in the Baltringen Formation (Middle Ottnangian, lower Miocene). In total, 27 genera could be identified (sharks: Alopias, Araloselachus, Carcharhinus, Carcharias, Carcharoides, Carcharodon, Centrophorus, Chaenogaleus, Galeocerdo, Hemipristis, Isistius, Mitsukurina, Nanocetorhinus, Notorynchus, Pachyscyllium, Pristiophorus, Pseudocarcharias, Rhizoprionodon, Scyliorhinus, Sphyrna, Squalus, Squatina; rays: Dasyatis, Raja, Rhinoptera, Rhynchobatos, Taeniurops). However, only taxa which were not already discussed in the previous publications are illustrated and described in this paper (14 taxa). Apart from Araloselachus, Carcharoides, Pachyscyllium and Nanocetorhinus, all have Recent relatives. The majority of the sharks and rays lived in the neritic realm, or this was part of their habitat. Only three genera (Isistius, Mitsukurina, Pseudocarcharias) have an oceanic lifestyle. For Nanocetorhinus, the habitat requirements are unknown. Galeocerdo and Notorynchus are omnivorous feeders, and Carcharodon feeds on fishes and also on marine mammals. All the others are/were invertebrate and/or fish feeders. With Nanocetorhinus sp., a rare taxon in the Molasse is verified as present. Large teeth over c. 2.5 cm in height are missing from the collection, but a comparatively large amount of (incomplete) squaliform teeth were found. The overall composition of the shark and ray fauna, together with the other fossils (bony fish and invertebrates) indicate a warm-temperate habitat in the neritic realm.
In this study we describe a new kitefin shark (Dalatiidae) genus and species Dracipinna bracheri gen. et sp. nov. based on upper Oligocene and lower Miocene tooth fossils. The teeth were excavated at three different sites which all lie in transgression phases. The fossil shark teeth are diverse and, depending on the excavation site, indicate pelagic to mesopelagic habitats. As these fossils were not found in older or younger sediments, we suggest a patchy distribution of the species. The fossils show several dental morphological characteristics of extant Dalatiidae. Phylogenetic analyses of combined morphological and DNA sequence-based data set suggest a weakly supported sister-group relationship of D. bracheri to extant Dalatiidae. Based on the dental morphological characters, we assign the dentition to a tearing type, which is rare among squaliform sharks and only known from a single extant species with a pelagic lifestyle. http://zoobank.org/urn:lsid:zoobank.org:pub:D4E3C807-8BEE-47EA-8DCA-6C8720ACAD0F
The sandpit near Rengetsweiler (Baden-Württemberg, SW Germany) is a famous locality for fossil shark and ray teeth from the Upper Marine Molasse (Lower Miocene). A total of 21 shark and ray genera were recovered from these sediments (Aetobatus, Alopias, Araloselachus, Carcharhinus, Carcharias, Carcharodon, Centrophorus, ?Dasyatis, Galeocerdo, Hemipristis, Isistius, Isurus, Mitsukurina, Notorynchus, Otodus (Megaselachus), Pachyscyllium, Physogaleus, Pseudocarcharias, Rhizoprionodon, Squatina, ?Triakis) as well as four specimens determinable as cf. Dasyatidae. The genera Araloselachus, Carcharoides, Otodus (Megaselachus), Pachyscyllium, and Physogaleus are extinct; all other taxa have living relatives. Based on extant representatives, the lifestyles of the ancient elasmobranchs range from a bottom-dwelling ambush predator (Squatina) to active swimming ones (Alopias, Carcharodon, Isurus, Otodus). Most of the taxa lived in the neritic realm. Members of Centrophorus, Isistius, Mitsukurina, and Pseudocarcharias are reconstructed as inhabitants of deeper water habitats. Based on Recent representatives and tooth shape, most of the taxa fed on invertebrates and/or fishes. Two taxa were dietary generalists (Galeocerdo, Notorynchus). Otodus fed on marine mammals. Carcharodon and adult Isurus also fed on marine mammals, in addition to fishes. Apart from the genera Centrophorus, Isistius, Mitsukurina, and Pseudocarcharias, the composition of the elasmobranch fauna as well as other fossil remnants and sedimentology indicate a fully marine, warm temperate and shallow water environment at the locality in the Lower Miocene. The normally deep-water taxa probably came occasionally into the shallow sea of Rengetsweiler.
Sibert and Rubin (Reports, 4 June 2021, p. 1105) claim to have identified a previously unidentified, major extinction event of open-ocean sharks in the early Miocene. We argue that their interpretations are based on an experimental design that does not account for a considerable rise in the sedimentation rate coinciding with the proposed event, nor for intraspecific variation in denticle morphology.
The newly collected shark and ray tooth fossils from the marine sediments of the Upper Marine Molasse close to Allerding (4.8 km SE of Schärding, Austria) allow for a review of the hitherto known diversity comprising a taxonomic update and the documentation of additional taxa. Besides ten taxa already known from the area, the following taxa were collected for the first time from the site: Galeocerdo aduncus Agassiz, 1835, Rhizoprionodon sp., Hemipristis serra Agassiz, 1835, Apristurus sp., Pseudoapristurus nonstriatus Pollerspöck & Straube, 2017, Scyliorhinus sp., Keasius sp., Mitsukurina lineata (Probst, 1879), Odontaspis molassica Probst, 1879, Otodus (Megaselachus) chubutensis (Ameghino, 1901), Chlamydoselachus bracheri Pfeil, 1983, Hexanchidae indet., Paraheptranchias repens (Probst, 1879), Notorynchus primigenius (Agassiz, 1843), Deania sp., Isistius triangulus (Probst, 1879), Euprotomicrus sp., Etmopterus sp., Pristiophorus sp., Nanocetorhinus tuberculatus Underwood & Schlögl, 2013, Raja gentili Joleaud, 1912, Rajidae sp. indet., Rhinobatos sp., Aetobatus arcuatus (Agassiz, 1843), and Dasyatis rugosa (Probst, 1877). Fossil teeth of Euprotomicrus represent the first fossil evidence of this taxon ever. Our results indicate a typical Miocene coastal shallow and continental shelf associated diversity. In addition, we reviewed the paleogeographic distribution ranges of the squaliform genera listed herein to test, if we can identify the origin of specific squaliform genera.
The North Alpine Foreland Basin (NAFB) comprises one of the most complete sedimentary records of the Oligocene and Miocene. Driven by global sea-level fluctuations, vast sedimentary influx and tectonic movement. The locality of Unterrudling near Eferding (Upper Austria) exposes the largest succession of sedimentary deposits from the late Oligocene in the eastern NAFB. Additionally, this section shows the facies transition from the shallow-water Linz-Melk Formation to the deep-water Eferding Formation. In this work, the fossil fauna and flora of the Eferding Formation as well as its lithology are re-evaluated using a multidisciplinary approach to gain new insights into the palaeoenvironment, palaeoclimate, and palaeoecology. A transgressive sequence is documented using sedimentological and ichnological data. Furthermore, a correlation to the late Chattian transgressive Ch-3 sequence is suggested. The impact of rising sea level on marine biota is shown in detail by analysing various groups (Bivalvia, Echinodermata, Anthozoa, Foraminifera, Chondrichthyes, Osteichthyes), with several newly reported species from the Eferding Formation. Moreover, washed in plant material was analysed for the interpretation of the terrestrial climate indicating mainly humid subtropical conditions. Finally, the presence of phosphatic nodules indicates eutrophication on the shelf environment and the possibility of upwelling currents.
Auch nach mehreren Jahrzehnten der Erforschung wartet die egerische Transgressionsabfolge von Unterrudling bei Eferding (Oberösterreich), welche den Übergang der Flachwasserablagerungen der Linz-Melk Formation zu den Tiefwassersedimenten der Eferding Formation (EF) umfasst, noch mit Überraschungen auf. So war kurzzeitig eine Schicht in der siltig-tonigen EF aufgeschlossen, die eine Vergesellschaftung von Tiefseekorallen und -bivalven enthielt und vermutlich den ältesten Nachweis dieser rezenten Biozönose darstellt. Dank neuer Funde und Analysen von Foraminiferen, Spurenfossilien sowie Knorpel- und Knochenfischen konnten die Umweltbedingungen und Ablagerungstiefen exakt rekonstruiert werden. Eine geochemische Analyse der phosphatischen Konkretionen in der EF deutet zudem auf eine Eutrophisierung des küstennahen Molassemeeres hin. Ein feuchtes, subtropisches Klima im spätoligozänen Alpenvorland konnte anhand der überlieferten Pflanzenfossilien nachgewiesen werden.
In the fossil record, sawsharks (family Pristiophoridae BLEEKER, 1859) include the genera Pristiophorus MÜLLER & HENLE, 1837, Pliotrema REGAN, 1906 and Ikamauius KEYES, 1979, which are mainly or exclusively represented by isolated lateral denticles of their saw-like rostra or less commonly (Pristiophorus) also by tiny oral teeth. We studied a large collection of fossil pristiophorid rostral denticles and oral teeth obtained from numerous localities exposing marine deposits of Rupelian to Tortonian age (Lower Oligocene to Upper Miocene) in the North Alpine Foreland Basin, North Sea Basin, Northeastern Atlantic and Central/northern Mediterranean Sea. In order to interprete the perceptible differences in tooth and denticle morphology of the fossil material, we conducted a parallel study on oral dentitions and rostral denticles in extant taxa of the Pristiophoridae. Representative samples of upper/lower oral teeth and of lateral/ventral rostral denticles are illustrated to document the heterodonty of teeth and characteristic features of denticles. In all species a gradient monognathic heterodonty is conspicuous. A dignathic heterodonty, typical of Pristiophorus spp., is mainly constituted by teeth in anteriormost files of the lower jaw that are larger and more strongly cambered labially than corresponding teeth in the upper dentition. Four new species are described: Pristiophorus borealis sp nov. from the Sülstorf Formation, early to middle Chattian, Mecklenburg, northeastern Germany; Pristiophorus austriacus sp nov. from the Ebelsberg Formation, Upper Egerian regional stage (Aquitanian), Upper Austria; Pristiophorus ungeri sp nov. from the Neuhofen Formation, lower Ottnangian regional stage (middle Burdigalian), Lower Bavaria, southern Germany and Pristiophorus tortonicus sp nov. from the Upper Mica Clay, early Tortonian, Schleswig-Holstein, northern Germany. For Pristiophorus suevicus JAEKEL, 1890, previously based on a lateral rostral denticle from the conglomeratic Baltringen Horizon, Baltringen Formation (middle Ottnangian, Burdigalian of southwestern Germany), we present a detailed description of oral teeth recovered from lower Ottnangian deposits of the North Alpine Foreland Basin. Palaeoenvironmental data of Paleogene and Neogene lithostratigraphic units (in a European geographical context) that commonly yield pristiophorid teeth/denticles suggest a preference of extinct sawsharks for middle to outer neritic and upper bathyal settings with soft (clayey, silty) bottoms, in agreement with the large depth range of most extant species on the middle to deep shelf and upper slope and the existence of a clear deep-water species (Pristiophorus schroederi) in the family.
The Early Ottnangian (Early Miocene, Burdigalian) marine deposit of Ursendorf (Baden-Württemberg, South Germany) belongs to the Upper Marine Molasse (UMM) unit in the Northern Alpine Foreland Basin. The outcropping sediments mainly consist of coarse-grained, poorly sorted sands, partly showing large-scale cross-bedding. In these sediments, 24 genera of sharks and rays could be identified (Aetobatus, Araloselachus, Carcharias, Carcharhinus, Carcharodon, Carcharoides, Centrophorus, Dasyatis, Echinorhinus, Galeocerdo, Hemipristis, Isurus, Otodus (Megaselachus), Mitsukurina, Myliobatis, Notorynchus, Odontaspis, Pachyscyllium, Physogaleus, Pseudocarcharias, Raja, Rhinoptera, Squatina, Taeniurops), five of which are extinct (Araloselachus, Carcharoides, Otodus (Megaselachus), Pachyscyllium, Physogaleus). Nearly all the taxa fed on invertebrates (squid, shrimps, etc.) and/or bony fishes. One taxon (Galeocerdo) is a more ‘generalistic’ feeder on invertebrates and fishes as well as on seabirds, snakes, turtles and marine mammals. Otodus (Megaselachus) and possibly also Carcharodon mainly preyed on marine mammals as well as bony fishes. The invertebrate remnants found in the same sediments (Mollusca, Bryozoa, etc.) as well as the bony fish teeth (Sparidae) indicate a typical soft-bottom community in temperate shallow water below the storm wave base. The rich invertebrate fauna and the bony fishes were a rich food supply for the sharks and rays. In order to compare Ursendorf with 16 other UMM localities in South Germany and Switzerland, a cluster analysis was conducted. In all of the three calculated indices, the Ursendorf shark fauna is most similar to that of Ballendorf, Baltringen, Ulm-Ermingen and Walbertsweiler (all in Baden-Württemberg), Benken (Switzerland) and Neuburg am Inn-Höch (Bavaria). This similarity can be explained by palaeogeographic and palaeoenvironmental features.
Deep-neritic sediments of the Eferding Formation (Egerian, Upper Oligocene) of Upper Austria from the Kamig kaolinite quarry revealed minute teeth of the putatively planktivorous shark genus Nanocetorhinus. This is the oldest unambiguous record of this rarely documented genus, which was known so far only from Miocene deposits of Europe, North America and Japan. Based on previous studies, which showed a positive correlation between sediments of nutrient rich waters and plankton blooms with a majority of ichthyoliths of Keasius and Nanocetorhinus, we argue for a filter-feeding and migratory lifestyle of the latter. Thus, it is supposed that Nanocetorhinus migrated seasonally for foraging, in a similar way to the extant basking shark Cetorhinus maximus. This mode of life and the wide paleogeographic distribution of the open marine genus Nanocetorhinus requires a deep and fully marine connection between the Paratethys and the Proto-Mediterranean Sea during late Oligocene times, which might have been established via the Slovenian Corridor.
An important character on several taxonomic levels for shark identification is the tooth morphology. Sharks show a variety of highly specialized dentitions reflecting adaptations to their feeding habits. Intraspecific variation of tooth morphology such as sexual or ontogenetic dimorphism is poorly known in many species, even though tooth morphology plays a decisive role in the characterization of the fossil record of sharks, which comprises mostly fossil teeth. Here we analyzed the dentition of 40 jaws of the Velvet Belly Lantern Shark Etmopterus spinax and identified ontogenetic and sexual dimorphic characters such as total number of teeth, number of upper teeth, cusplet numbers in upper jaw teeth and width of lower jaw teeth. Dimorphic characters may reduce intraspecific competition for food, as E. spinax segregates by sex and size and may allow for identifying the male sex. The lower jaw tooth height, a sexually non-dimorphic character, was used to recalculate the total length of specimens, which represents the first such approach for a squaliform shark. Results derived from the extant E. spinax are subsequently applied to fossil Etmopterus sp. teeth (Miocene) to gain individual information such as sex or size, but also characterize the extinct population from the excavation site by a size distribution profile in comparison to data from extant populations. This approach indicates the presence of multiple ontogenetic stages in the extinct population.
Elasmobranch remains are quite common in Miocene deposits and were the subject of numerous studies since the middle of the nineteenth century. Nevertheless, the taxonomic diversity of the Marine Molasse sharks, rays and skates is still largely unknown. Here, we describe 37 taxa from the lower Miocene of the Molasse Basin: 21 taxa could be identified at species level, whereas 15 taxa could only be assigned to genus and one taxon is left as order incertae sedis. The material was collected from deposits of the Auwiesholz Member of the Achen Formation (middle Burdigalian, middle Ottnangian age, ca. 17.8 Ma) exposed near Simssee, Upper Bavaria. This faunal assemblage is a mixture of shallow marine, near-coastal, pelagic and deep-water taxa. The fauna from Simssee displays different biogeographic dynamics at local and regional scales, possibly related to the intense climatic, oceanographic and tectonic events that occurred during the Eggenburgian–Ottnangian stages. The faunal relationships of the early Miocene chondrichthyan faunas from the Mediterranean Sea and Paratethys with others regions are established on the basis of qualitative (presence/absence) data. The beta diversity (Sørensen–Dice coefficient) of the Miocene Molasse elasmobranchs was used to characterize the taxonomic differentiation between localities and regions. According to our results, the fauna from Simssee shows close similarities with those from Switzerland, Austria, France and northern Germany. Faunal similarities and differences are mainly related to tectonic events and oceanographic variables (i.e. migration through seaway passages) or might represent collecting biases.
Continuous prospecting of an active quarry located in Upper Austria (North Alpine Foreland Basin) provided a rare assemblage of well-preserved isolated teeth of elasmobranchs. The fossiliferous sediments are part of the upper Oligocene (Egerian) Eferding Formation and represent an outer neritic depositional environment. The assemblage comprises six elasmobranch genera (Hexanchus, Carcharias, Araloselachus, Isurus, Galeocerdo, and Carcharhinus), which increases the number of taxa known from the Eferding Formation significantly. We present a synthesis of the Egerian elasmobranch fauna of the Austrian part of the North Alpine Foreland Basin recovered from the Eferding, Ebelsberg, and Linz-Melk Formations and report the first records of Hexanchus agassizi, Galeocerdo aduncus, and Carcharhinus gibbesii from the late Oligocene of Austria.
Elasmobranchs (sharks, rays, and skates) have been the predominant predators of the Central Paratethys during its fully marine phases in the Oligocene and Miocene. Whilst middle and upper Miocene strata are frequently outcropping in the Austrian part of the North Alpine Foreland Basin (NAFB), upper Oligocene and lower Miocene sediments of the Egerian stage are less frequent. Consequently, the knowledge on the fauna of these mainly outer neritic deposits is rather limited. Here, we present elasmobranch teeth of a new outcrop of the Eferding Formation. The sediments are exposed in the active quarry of the Kaoline mining company KAMIG in Kriechbaum near Allerheiligen im Mühlkreis (Upper Austria). These have been intensively screened by collectors regarding its fossil content. The accompanying invertebrate fauna consists of bivalves (e.g. Pectinidae, Anomiidae) and echinoderms (Cidaridae). Along with numerous teleost remains have been detected (vertebra, otoliths, and teeth), the assemblage comprises teeth of six elasmobranch genera (Hexanchus, Carcharias, Araloselachus, Isurus, Galeocerdo, and Carcharhinus), which increases the number of taxa known from the Eferding Formation significantly (Feichtinger et al. 2019). Continuing screen washing of four different levels of the quarry revealed further elasmobranch taxa of the families Scyliorhinidae, Rajidae, and a presumably new species of Nanocetorhinus (Neoselachii incertae sedis, family incertae sedis). These results document the importance of screen washing of large sediment samples to detect also small taxa.
Fossil upper and lower squaliform shark teeth from the upper Austrian marine Molasse (Paratethys, Upper Egerian, Aquitanian) were collected. For testing the phylogenetic signal of 31 reviewed dental characters of both fossil and extant etmopterids and somniosids, we performed phylogenetic analyses using both parsimony and maximum likelihood approaches. The results indicated a close phylogenetic relationship of teeth collected for this study with the extant somniosid genus Centroscymnus. A number of preliminary or un-identified fossil teeth published in other studies were included in our analyses and clustered along with the fossils described herein, suggesting a synonym. Our results further allow for a revision of the type species of Paraetmopterus horvathi Underwood and Schlögl, 2013 and the description of Palaeocentroscymnus gen. nov.
This article describes the oldest record of a tooth of the shark genus Oxynotus from Europe. Oxynotus, Miocene, new record, Germany, Europe,
In this study, a diverse fauna of fossil elasmobranch teeth from the Early Miocene (Middle Burdigalian) is analysed. The fossil diversity strongly resembles extant deep-water shark and ray assemblages. The fossils were collected from the Upper Marine Molasse of the lower Ottnangian in the Neuhofener Beds location, Mitterdorf, Germany. The collection site is a clay pit in between the Lower Bavarian villages Fürstenzell and Schmidham. The sample revealed 14 shark and four ray species. We present the first record of fossils assigned to taxa Nanocetorhinus tuberculatus, Deania and Apristurus from Germany. In addition, we describe a hitherto unknown genus and species of shark, Pseudoapristurus nonstriatus gen. et sp. nov., based on fossil teeth. The documented diversity is compared to both extant and fossil records of neoselachian deep-water diversities, and it is evident that this Miocene fauna is very similar in composition to indo-pacific deep-water assemblages. Key words: Bavaria, Early Miocene, deep-water, Chondrichthyes, Ottnangian, Burdigalian, Upper Marine Molasse
A rich assemblage of elasmobranch teeth of Early Miocene age (Ottnangian, Upper Marine Molasse) is described from the Heigelsberger Ditch near Teisendorf (Upper Bavaria, Germany). The fauna includes 13 shark and 4 batoid species, including Centrophorus cf. granulosus, Isistius triangulus, Squalus sp., Pristiophorus suevicus, Squatina sp., Mitsukurina lineata, Alopias exigua, Carcharhinus priscus, Hemipristis serra, Chaenogaleus affinis, Iago angustidens, Premontreia sp., Carcharias acutissimus, Raja sp., Dasyatis rugosa, Dasyatis probsti, and Myliobatis sp., which are reported for the first time from the Upper Bavarian part of the Subalpine Molasse Basin.
A single bed of conglomeratic, fossil-rich marls intercalated in siliciclastic Lower Egerian deposits (informally denoted as Thalberg Beds, middle to late Chattian, Late Oligocene) yields a diverse elasmobranch fauna. The conglomeratic bed is exposed in the Thalberg Graben, a few km south of Traunstein, Upper Bavaria. It forms part of the Lower Marine Molasse, deposited in the North Alpine Foreland Basin representing the western prolongation of the Central Paratethys. 22 shark and 5 batoid taxa were recognized, of which 16 and 1, respectively, could be identified to species level. Shark species related to living taxa, actively swimming and foraging in the water column of the neritic zone (Notorynchus, Carcharias, Isurus, Galeorhinus, Alopias, Galeocerdo, Carcharhinus, Squalus and probably the fossil genera Otodus (Carcharocles), Araloselachus, Physogaleus and Carcharoides), dominate the fauna both by the number of observed taxa and collected teeth. Species of planktivorous sharks and batoids are few and their gill rakers (Keasius) and teeth (Mobula, Megachasma) are very rarely encountered. Sharks and batoids inhabiting present-day and past benthic or epibenthic habitats, typically of warm-temperate shelf seas, are strongly underrepresented (scyliorhinids, dasyatids, myliobatids) or completely absent (rajoids) in the Thalberg assemblage. On the other hand, various taxa of deep-water sharks (Hexanchus, Heptranchias, Echinorhinus, Centrophorus) are variably common. The composition of the Thalberg elasmobranch assemblage differs significantly from well documented assemblages of the Chattian warm-temperate/subtropical North Sea shelf, mainly with respect to shallow-marine, benthic and deep-water species.