Coccolith biostratigraphy based on archival assemblages of Miocene deposits from Gdów tectonic embayment of Polish Carpathian Foredeep

W próbkach Brzezie 20/06 oraz 19/06, pochodzących z obszaru zatoki gdowskiej, wykryto 16 różnych gatunków nanoplanktonu. Taksony zostały opisane pod kątem morfologii, zaś do opisów dołączono zdjęcia, wykonane pod mikroskopem optycznym. Przy wykorzystaniu zasięgów występowania taksonów oraz skonstruowaniu diagramu, udało się wstępnie określić ramy czasowe próbki na serrawal. Następnie, w oparciu o metodę biostratygraficzną wykorzystującą nanozony oraz wydarzenia związane z pojawieniem się lub zanikiem poszczególnych taksonów, zaproponowano wiek próbki na około 13-12 mln lat. Wykorzystując informacje o występowaniu poszczególnych gatunków, udało się określić warunki basenowe jako umiarkowanej żyzności, stosunkowo niskiej bioróżnorodności, o chłodnej lub umiarkowanie ciepłej wodzie oraz o znacznym udziale terygeniczej dostawy materiału.In samples Brzezie 20/06 and 19/06, coming from Gdów embayment, 16 species of coccolith-bearing organisms were identified. They were described by morphology, with photos made under optic microscope included. Through using age ranges and constructing diagram, time margin of sample was found to be Serrevalian. Through biostratygraphic method using nanozones and events connected to occurrence or disappearance of specific taxon, an age of 13-12 Ma years was proposed. Using information about occurrence of specific species, basin conditions were found to be moderately fertile, with relatively low biodiversity, with cool or temperate water and with significant contribution of terrigenous material supply

Microstructural characteristics and seasonal growth patterns observed in Metoposaurus krasiejowensis teeth

The tooth microstructure of Metoposaurus krasiejowensis was studied to observe external morphology, internal microstructure (comprising dentine structure and directional porosity as possible predatory adaptations) and enamel/enameloid mineral composition. Scanning electron microscopy (SEM) observation and thin-section inspection by light microscope enabled us to recognize a directional porosity in the tooth cross-sections, interpreted here as a part of the labyrinthodont structure displayed by temnospondyls and related groups. This network of canals is highly complicated and reveals a three-dimensional structure. The teeth present different cross-sections based on the distance from the tip, with a wide, circular, reinforced base and lateral compressed, directional cuspidal section with cutting edge. Interestingly, the internal structure observed in M. krasiejowensis teeth exhibit a peculiar variation of internal structure of temnospondyl teeth, as the convoluted canal-like structure seems to be irregular and appears in the upper section of teeth, while teeth bases show a regular structure with a pulpal cavity circled by pores. Furthermore, bands of incremental growth marks interpreted as Andresen lines, characterized by pronounced colour variation, were observed with strong implications for seasonal growth patterns in dentine. Additionally, a significant proportion (1.43–2.73%) of fluoride was observed as a component of enamel by scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS) point and mapping analyses, suggesting a fluorapatite mineralogy of enamel