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EN
Fossil vertebrate remains from the Keuper unit in the vicinity of the village of Krasiejów have been analyzed for almost two decades. However, the main goal of these works was focused mainly on large vertebrates. Here the authors present the first description of microvertebrate fossils from that site. The collection of around 5,000 specimens is mainly comprised of teeth and scales. The most numerous remains belong to osteichthyans: dipnoans (Ptychoceratodus and cf. Arganodus), palaeoniscids, semionotids, redfieldiids and chondrichthyans, such as Lonchidion sp., which is the first indisputable record of that genus in the Upper Triassic of Poland and the first shark at the Krasiejów locality. Tetrapod fossils consist of temnospondyl amphibians, rhynchocephalian lepidosauromorphs and archosauromorphs. Among them, temnospondyl amphibian remains are the most numerous and are represented mostly by Metoposaurus. However, on the basis of diversity in tooth morphotypes, the occurrence of other taxa cannot be excluded. Rhynchocephalians are composed of 7 fragmentary jaw morphotypes with dentition, which could indicate high taxonomic diversity (cf. Planocephalosaurus, cf. Diphydontosaurus and cf. Clevosaurus). The most varied fossil group was assigned to the archosauromorphs. The authors can distinguish at least 19 teeth morphotypes, which show similarities to the dentition of: protorosaurians (cf. Tanystropheidae), pseudosuchians (cf. Protecovasaurus, cf. Revueltosaurus), early crocodylomorphs and basal sauropodomorph dinosaurs. The first occurrence of a theropod dinosaur and cynodonts at the Krasiejów locality is also recorded. However, their remains are very rare. These new records show a high taxonomic diversity at the Krasiejów locality that contributes to our deeper understanding of Late Triassic ecosystem of Poland.
EN
The major goal of the project “The evolution of terrestrial environments of the Upper Silesian Keuper as biotopes of vertebrates”, granted for Grzegorz Racki by the Ministry of Science and Higher Education (2009-2013), was an exhaustive, integrated study of the bone-enriched middle Keuper interval in terms of stratigraphy, sedimentology, mineralogy and geochemistry. The new website “Bone-bearing Keuper of the Upper Silesia, southern Poland” (http://www.ing.pan.pl/Keuper/Bone-bearing_Keuper-1.htm)presents in English the results of this project. The significant achievements are only a starting point to a comprehensive presentation of the complex Keuper themes, jointly with an extensive repository of regional literature (above 420 full-texted publications since 1790). In addition, the main results of the grant, as well as diversity of their implications for future studies are summarized herein, with emphasis on controversial geochronological aspects in vertebrate paleontology (how many bone-rich levels?), and in a broad historical context.
EN
Magnetostratigraphy of the Keuper succession in the southern Mesozoic margin of the Holy Cross Mountains is presented based on investigations of two sections of Brzeziny and Wolica. They cut an ~60 m thick succession of variegated siltstones and claystones, which overlies the Reed Sandstone (Stuttgart Formation). The succession has been correlated with the Patoka Member of the Grabowa Formation, defined in the Upper Silesia region as an equivalent of the Steinmergelkeuper (Arnstadt Formation). The primary Late Triassic magnetization was obtained from component B carried by fine-grained haematite. Twelve magnetic polarity zones, six of normal and six of reversed polarity, have been defined. The obtained polarity pattern corresponds to the Norian (E13–E16 Newark zones) according to the Long-Rhaetian option of the Late Triassic Magnetic Polarity Time Scale. The mean normal polarity characteristic direction (N = 24, D/I = 31/62, k = 28.24, α95 = 6.04) differs significantly from the reversed one (N = 18, D/I = 223/-25, k = 16.38, α95 = 8.65): the primary magnetic signal is partly overlapped by component A carried by magnetite of recent viscuous remanent magnetization. Some samples do contain also coarse-grained haematite that, however, does not form any clustered magnetization. The palaeopole position calculated from the transposed reversed and normal polarity directions of component B corresponds to the Late Triassic (Norian) segment of the reference Baltica/Europe Apparent Polar Wander Path.
EN
The Upper Triassic Kågeröd Formation of Bornholm consists of clays, sandstones and conglomerates of floodplain and fluvial origin, but details of the depositional environment are poorly understood. Trace fossils are described for the first time from the red and green clays (floodplain with lake deposits) and cross-stratified sandstones (fluvial channel deposits) of the Upper Triassic Kågeröd Formation on Bornholm, Denmark. The sparse ichnofauna consists of large, mud-filled shafts and tunnels in caliche-bearing conglomerate, determined as Camborygma and attributed to the burrowing activity of cray fish. The sandstones preservevertical U-shaped burrows passively filled with sand, assigned to Arenicolites and probably produced by insects. Furthermore, they contain winding, horizontal, oblique and vertical unbranched burrows with an active meniscate sandfill, referable to Taenidium and supposedly produced by burrowing beetles. The clays and the sandstones contain numerous caliche nodules of centimetre to decimetre size, some of which contain root traces in the form of rhizoliths. This trace-fossil association reflects deposition on a vast floodplain with shallow lakes and fluvial channels, under semiarid conditions.
EN
Vertebrate remains, mostly nothosaurid vertebrae and long bones, archosaur partially preserved long bones and teeth (probably rauisuchid remains), fish teeth and scales, are described from the Lower Keuper Miedary Beds (Ladinian, Middle Triassic) of Miedary, Silesia, SW Poland. The analyzed vertebrate fossils were collected from three lithologically different types of deposits. The first assemblage, which contains nothosaurid and fish remains, occurs in yellowish dolomites, where poorly preseved invertebrate macrofossils were also found (marine bivalves and brachiopods). In grey-yellowish, sometimes greenish or red clays, rare isolated bones and teeth of large archosaur were found. In sandstone intercalations partially preserved and highly disarticulated fish fossils were identified. In all assemblages osteological remains are generally very well preserved. This new interesting vertebrate bones association from the upper part of the Middle Triassic marginal-marine strata of Poland has been correlated with age-equivalents from other regions of Europe.
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