The trace fossil Lepidenteron lewesiensis: a taphonomic window on diversity of Late Cretaceous fishes

The trace fossil Lepidenteron lewesiensis (Mantell 1822) provides an exceptional taphonomic window to diversity of fishes as shown for the Upper Cretaceous of Poland, in the Middle Turonian–Lower Maastrichtian deposits of the Opole Trough, Miechów Trough, Mazury-Podlasie Homocline, and SE part of the Border Synclinorium. Lepidenteron lewesiensis is an unbranched burrow lined with small fish scales and bones, without a constructed wall. It contains scales, vertebrae, and bones of the head belonging to ten taxa of teleostean fishes: two undetermined teleosteans, six undetermined Clupeocephala, one Dercetidae, and one undetermined euteleostean. The preservation of fish remains suggests that fishes were pulled down into the burrow by an animal, probably by eunicid polychaetes.Das Spurenfossil Lepidenteron lewesiensis (Mantell 1822) ermöglicht einen biostratinomischen Einblick in die Diversität von Fischen, wie Fossilmaterial aus der Oberkreide von Polen zeigt. Es stammt aus dem Mittelturonium bis Untermaastrichtium des südöstlichen Abschnittes der Grenz-Synklinale, dem Opolen-Trog, dem Miechów-Trog und der Masuren-Podlachien-Homoklinale. L. lewesiensis ist ein unverzweigter Grabgang ohne ausgekleidete Wände, dessen Ränder von kleinen Fischschuppen und—knochen gebildet werden. Diese setzen sich aus Schuppen, Wirbel und Schädelknochen von zehn Teleostei-Taxa zusammen und zwar aus zwei unbestimmte Teleosteer, sechs unbestimmten Clupeocephala, einem Dercetidae und einem unbestimmten Euteleostei. Die Erhaltung der Fischüberreste deutet darauf hin, dass die Fische von einem Tier, wahrscheinlich einem Polychaeten der Familie Eunicidae, in den Bau gezogen wurden.We are very grateful to Dr. Lionel Cavin (Geneva) and the anonymous reviewer for constructive comments on an earlier version of the manuscript. Additional support was provided by the Jagiellonian University (DS funds), National Science Center (Grant Number: PRO-2011/01/N/ST10/07717), and the Laboratory of Geology (University of Lodz) BSt Grant No. 560/844. We are grateful to Dr. Johann Egger (Wien) and Kilian Eichenseer M.Sc. (Erlangen) for help with translating the abstract into German. We are grateful to Dr. Ursula Göhlich (Wien) for access to the Dercetis specimen

Artificial Kohonen neural networks as a tool in paleontological taxonomy - an introduction and application to Late Cretaceous belemnites

Artificial neural networks (ANNs), the computer software or systems that are able to "learn" on the basis of previously collected input data sets are proposed here as a new useful tool in paleontological modeling. Initially ANNs were designed to imitate the structure and function of natural neural systems such as the human brain. They are commonly used in many natural researches such as physics, geophysics, chemistry, biology, applied ecology etc. Special emphasis is put on the Kohonen self-organizing mapping algorithm, used in unsupervised networks for ordination purposes. The application of ANNs for paleontology is exemplified by study of Late Cretaceous belemnites. The Kohonen networks objectively subdivided the belemnite material] ~ 750 specimens) into consistent groups that could be treated as monospecific. The possibility of transferring these results to the language of classical statistics is also presented. Further development and possibility of use of ANNs in various areas of paleontology, paleobiology and paleoecology is briefly discussed

The Belemnitella stratigraphy of the Upper Campanian : basal Maastrichtian of the Middle Vistula section, central Poland

This taxonomy and stratigraphy of the Upper Campanian and Lower Maastrichtian Belemnitella lineages, from the Middle Vistula sections, based on new collections, is presented. The correlation to the basal Maastrichtian standard GSSP at Tercis, France, is provided based on inoceramid bivalve stratigraphy. The Artificial Neural Networks (ANN), particularly the self-organizing Kohonen algorithm, was applied to taxonomic discrimination. Eight morphotypes within the genus Belemnitella, understood here as natural species populations, were recognised. Five of these are assigned to known taxa: Belemnitella mucronata, B. posterior, B. minor [= B. minor I and B. minor II], B. langei and B. najdini; and three, B. sp. a, B. sp. 1 and B. sp. 2, are left in open nomenclature. Four Belemnitella zones are proposed. Due to its palaeogeographic position, between Western and Eastern Europe, the Middle Vistula section is characterized by the co-occurrence of Belemnitella species from those two areas. Consequently, it enables better correlation of Belemnitella-based schemes; the East European B. najdini and B. posterior are placed next to West European B. minor chronospecies I and II. The Campanian/Maastrichtian boundary, as currently defined, is placed at the top of the najdini – posterior Zone, which is an equivalent of the Belemnella-based boundary, i.e. at the base of the Belemnella obtusa / Belemnella vistulensis zones. Within the top of the najdini – posterior Zone occurs a level (an interval of only a few metres), where nearly all of the Upper Campanian Belemnitella disappear. This level coincides with taxonomic changes observed within the co-occurring representatives of genus Belemnella

The Belemnella stratigraphy of the Campanian-Maastrichtian boundary; a new methodological and taxonomic approach

The taxonomy and stratigraphy of the Upper Campanian and Lower Maastrichtian belemnites from the Vistula (central Poland) and Kronsmoor (northern Germany) sections are revised on the basis of new collections from the Vistula section as well as a reinvestigation of the classic collection of Schulz from the Kronsmoor section. For the taxonomic description a new biometric procedure is proposed, which can be applied to both the genera Belemnella and Belemnitella. For the species-level taxa recognition the Artificial Neural Networks method, the self-organizing Kohonen algorithm, was implemented. This new taxonomic and methodological approach enabled the recognition of nine species of the genus Belemnella. Five of them can be assigned to the existing species B. lanceolata, B. longissima, B. inflata, B. obtusa and B. vistulensis. However, the species concept differs from that applied by Schulz (1979). As a consequence, the stratigraphic ranges of these species are modified. Four species are left in open nomenclature and represent possibly new species. Future studies may reveal that they might be assigned to East European forms from Ukraine or Russia. The species of Belemnella recognized are placed into the stratigraphic framework based on the standard ammonite and inoceramid bivalve zonations, especially those recognized in the Vistula section. The newly proposed belemnite zonation for the Vistula and Kronsmoor sections is correlated via inoceramids with the standard GSSP at Tercis, France, in order to identify the base of the Maastrichtian Stage. The Campanian/Maastrichtian boundary as defined in Tercis is placed here at the base of the newly defined B. obtusa and B. vistulensis Zones ["obtusa/vistulensis"] - thus it is markedly higher than the traditional boundary based on the FAD of representatives of the genus Belemnella - This new boundary coincides well with a distinct turnover of belemnite guard morphology and represents one of the most important points in the early evolutionary history of Belemnella. Three belemnite zones defined by their lower boundaries are recognized in the Campanian/Maastrichtian interval, in addition to three subzones recognized within the B. obtusa Superzone. The B. lanceolata and B. inflata zones as understood here are referred to the Upper Campanian [Tercis definition]. The B. obtusa Zone is subdivided into three subzones, viz.: Belemenlla vistulensis, Belemnella sp. G and Belemnella sp. F, which are referred to the Lower Maastrichtian [Tercis definition]. The fast evolving species of Belemnella enable the proposal of a biostratigraphic scheme with a resolution that is higher than those based on inoceramid bivalves and ammonites - the longevity of a belemnite zone could be as low as 200Ky

Gigantic theropod dinosaur footprints from the upper Pliensbachian of the Holy Cross Mountains, Poland

New gigantic theropod dinosaur footprints were discovered in the upper Pliensbachian deposits of the Holy Cross Mountains (Poland). This discovery provides new ichnological evidence for the global occurrence of gigantic predatory dinosaurs in the earliest Jurassic time. Interestingly, this is the third find of gigantic theropod ichnites in the Lower Jurassic of Poland. The first record of gigantic tracks from this area came from the well-known lower Hettangian tracksite in Sołtyków. New finds from the Szydłówek quarry were discovered in siliciclastic strata, which are interpreted as nearshore, shoreface and marginal marine. Hitherto, five isolated specimens of gigantic theropod footprints (40–60 cm long) were found in this tracksite. Another large theropod footprints (30–40 cm) identified at Szydłówek, resemble classic theropod ichnotaxa of the Newark Supergroup (i.e., Eubrontes). Intriguing gigantic theropod ichnites from the Holy Cross Mountains are more similar to large prints left byMiddle and Late Jurassic theropods than to those from the Early Jurassic. These footprints seem even larger because of their large metatarsophalangeal area. Relatively large metatarsophalangeal area is often observed in the large theropod footprints from the post-Liassic strata. New paleoichnological finds from Poland suggest rapid increase of predatory dinosaur body size in Early Jurassic time

Early representatives of the belemnite genus Belemnella (Cephalopoda) from the uppermost Campanian-Lower Maastrichtian of the Middle Vistula River section, central Poland

Representatives of the belemnite genus Belemnella from the uppermost Campanian and lowermost Maastrichtian of the Middle Vistula River Valley section (central Poland) have been studied, using the species concept proposed by Schulz in 1979. Results have been compared to a recently proposed new interpretation of the genus Belemnella based on artificial neural networks, as put forward by Remin in 2007 and 2012. In the interval studied, four taxa have been recognised: Bln. longissima, Bln. inflata, Bln. obtusa and Bln. vistulensis, the last-named being a senior synonym of Bln. pseudobtusa. Three additional forms have been left in open nomenclature: Bln. cf. lanceolata, Bln. ex gr. lanceolata/inflata and Belemnella sp. Based on their documented vertical ranges, three Belemnella standard zones, as originally distinguished in the Kronsmoor section by Schulz (1979), northern Germany, have been defined, in ascending order: the Bln. lanceolata, Bln. vistulensis and Bln. obtusa zones. The bases of the lanceolata and obtusa zones in the Middle Vistula River Valley section can be directly correlated with the same zones at Kronsmoor, and appear to be isochronous within limits of stratigraphic resolution. The base of the vistulensis Zone (Bln. vistulensis according to the species concept of Schulz in 1979), however, is probably diachronous, being older in the Middle Vistula section. Although Schulz's and Remin's species concepts differ quite considerably, they do result in similar stratigraphic subdivisions of the Kronsmoor and Middle Vistula River sections

Integrated biostratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland

The biostratigraphic importance, current zonations, and potential for the recognition of the standard chronostratigraphic boundaries of five palaeontological groups (benthic foraminifers, ammonites, belemnites, inoceramid bivalves and echinoids), critical for the stratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland, are presented and discussed. The summary is based on recent studies in selected sections of southern Poland (Nida Synclinorium; Puławy Trough including the Middle Vistula River composite section; and Mielnik and Kornica sections of south-eastern Mazury-Podlasie Homocline) and of western Ukraine (Dubivtsi). The new zonation based on benthic forams is presented for the entire interval studied. Zonations for ammonites, belemnites and inoceramid bivalves are compiled. All stage boundaries, as currently defined or understood, may easily be constrained or precisely located with the groups discussed: the base of the Santonian with the First Occurrence (FO) of the inoceramid Cladoceramus undulatoplicatus; the base of the Campanian with the Last Occurrence (LO) of the crinoid Marsupites testudinarius and approximated by the range of the foraminifer Stensioeina pommerana; and the base of the Maastrichtian approximated by the FO of the inoceramid bivalve Endocostea typica and the FO of the belemnite Belemnella vistulensis. The positions of substage boundaries, as currently understood, are constrained in terms of the groups discussed

Changes in paleo-circulation and the distribution of ammonite faunas at the Coniacian–Santonian transition in central Poland and western Ukraine

Ammonite distribution patterns and carbon and oxygen stable isotopes from the Lipnik-Kije (Poland) and Dubovcy (Ukraine) sections allow us to propose a model of sea water paleo-circulation in central Europe for the Coniacian-Santonian interval. The tectonic evolution of the south-eastern part of Poland, and expansion of the Krukienic Island areas, appears to have been one of the most important factors affecting paleotemperatures and the distribution of ammonite faunas in the shallow, epicontinental sea in this part of Europe. In the Lipnik-Kije section, low-latitude Tethyan ammonites, especially of the genera Nowakites, Parapuzosia and Saghalinites, are mixed with the cold water loving ammonite genus Kitchinites in the Lower Santonian. In the Dubovcy section (western Ukraine), Tethyan ammonites disappear abruptly in the earliest Santonian, giving place to temperate ammonites of the Kitchinites group in the early Early Santonian and to Boreal belemnites of the genus Gonioteuthis in the Middle and Late Santonian. Despite evidence for the effects of diagenesis in both sections, bulk-rock δ18O records from the limestones support higher seawater paleotemperatures in the Polish sea and cooler conditions in the western Ukraine. The proposed paleo-circulation model and paleotemperature distribution across Europe is supported independently by changes in faunal and nannoflora evidence (ammonites, foraminifera and nannoplankton), and rather unexpectedly with the bulk δ18O data. These data allow the recognition of the end-Coniacian–Early Santonian cooling event, resulting from cold currents flowing from the north, which is traceable, with different magnitude, in several European sections. Facies changes in both sections are related to the input of terrigenous material, and linked to Subhercynian tectonic movements which affected the eastern (Ukrainian) and central (Holy Cross) segment of the Mid Polish Trough at different times. Uplift and sediment input moved westwards through time. Clastic input is detectable at the Coniacian–Santonian boundary in the Ukrainian segment. Similar facies changes reached the Holy Cross segment in Poland distinctly later, somewhen in the Middle Santonian. It is likely that tectonics together with paleo-circulation changes markedly restricted or even cut-off the western Ukraine area from Tethyan ocean influences in the Early Santonian

The stratigraphically earliest record of Diplomoceras cylindraceum (heteromorph ammonite) : implications for Campanian/Maastrichtian boundary definition

A fragmentary specimen of the diplomoceratid heteromorph Diplomoceras cylindraceum, one of three ammonite markers used for the definition of the base of the Maastrichtian Stage, is recorded from the middle Campanian of the Roztocze Hills, southeast Poland. The new find, well constrained by associated ammonites and inoceramid bivalves, represents the earliest well-dated occurrence of this species worldwide to date. Therefore, the first occurrence (FO) of D. cylindraceum is conspicuously below the traditional base of the Maastrichtian as defined by the FO of the belemnite Belemnella lanceolata. Indeed, this is also far below the boundary designated in the Global Stratotype Section at Tercis les Bains (Landes, France). A comparison of the FOs of D. cylindraceum in sections acrossEurope clearly shows a significant diachroneity, which diminishes its value for definition of the Campanian/Maastrichtian boundary

New finds of dinosaur tracks in the Liassic strata of the Holy Cross Mountains, Poland

New Lower Jurassic material of dinosaur tracks has been found in the coastal siliciclastic and fluvial deposits of the Holy Cross Mountains (HCMts.), Poland. Three poorly preserved specimens of small to medium-sized theropod dinosaur footprints, assigned to cf. Grallator isp. and cf. Anchisauripus isp.,were found in the Sinemurian deposits exposed in the Starachowice outcrop. Sixteen specimens of dinosaur tracks, referred to ichnotaxa cf. Grallator isp., Anchisauripus isp., cf. Kayentapus isp., cf. Moyenisauropus isp., Theropoda indet., and Dinosauria indet., have been found in the upper Hettangian deposits of the Przysucha Ore-Bearing Formation and the Lower Sinemurian Ostrowiec Formation exposed near Żarnów (Paszkowice and Żarnów sites) in the northwestern part of the HCMts. Dinosaur footprints (cf. Anchisauripus isp., cf. Kayentapus isp.; and cf. Moyenisauropus isp.) and non-dinosaur tracks were found at the Bielowice site, known also as Wólka Karwicka near Opoczno. Interesting large ornithischian footprint (cf. Moyenisauropus isp.) and small-medium theropod footprints (Anchisauripus isp.) were found in the Zagaje Formation of Chyby near Mniów. Ornithischian dinosaur tracks similar to Moyenisauropus were also found in Skłoby Formation at Szwarszowice near Ostrowiec Świętokrzyski. The last finds reported herein, the well preserved specimens of Anomoepus, Anchisauripus, Eubrontes and Kayentapus-like footprints, came from the new tracksite of Szydłówek. Tracks made by large theropods (cf. Megalosauripus isp.) and sauropods were also found at this site. The material came from the strata representing a large barrier-lagoon/deltaic sequence. These new finds confirm that the barrier-lagoonal association of theropod dinosaurs of the Lower Jurassic of the HCMts. is characterised by dominance of small and medium-sized forms but contains also prints made by larger animals. The analysis of the Liassic ichnocenosis suggests that Anchisauripus was a facies-independent ichnotaxon. In the Lower Jurassic of Poland this ichnogenus was identified in the fluvial (aluvial-plain), deltaic (delta-plain), and barier-lagoonal deposits