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EN
Fern remains of matoniacean affinity were found in the Lower Hettangian strata of lacustrine/backswamp origin from the Niekłań PGI 1 borehole (central Poland, Holy Cross Mts.). The preserved fragments have been identified as Matonia braunii (Göppert, 1841) Harris, 1980. The remains suggest a rather small, low-growth plant with palmately compound fronds. The sori contain at least 5 sporangia preserved with well-developed annuli. The spores are triangular, trilete and kyrtomate, with a thin and smooth surface corresponding with dispersed Dictyophyllidites mortoni (de Jersey, 1959) Playford et Dettmann, 1965. Based on the gross morphology of sterile and fertile pinnae, suggestions made by Harris (1980) on the synonymy of Phlebopteris braunii (Göppert, 1841) Hirmer et Hörhammer, 1936 with P. muensteri Schenk, 1867 (Hirmer and Hörhammer, 1936) and their referral to Matonia braunii is proved and confirmed in this paper. The fern occurs in strata indicating a warm and humid climate and approaching transgression resulting in a high water table and the enhanced accumulation of organic matter.
EN
Plant macroremains from five boreholes in Poland were studied. Two of them (Huta OP-1 and Studzianna) from the northern margin of the Holy Cross Mountains, yielded several taxa. In the other three boreholes determinable fossil plants were sporadic, albeit important. Most of the taxa from the Huta OP-1 and Studzianna boreholes are typical of the European Early Jurassic (Hettangian and Sinemurian). Both localities, although close to one another, show quite different taxonomic floral compositions. The Huta OP-1 flora is fern-dominated with the presence of ginkgophytes and conifers (a new species incertae sedis, Desmiophyllum harrisii Barbacka et Pacyna is herein proposed), which would suggest rather wet and warm conditions. This flora is typical of the European Province of the Euro-Sinian Region. In Studzianna the Siberian elements dominate, gymnosperms, mainly Czekanowskiales, which indicate a drier and colder environment.The palaeobotanical data correspond to the results of clay mineral studies, in particular the kaolinite/illite ratio in the source formations. The kaolinite content confirms a decrease in temperature and a reduction in rainfall in the late Early Hettangian and the latest Hettangian in the area.
EN
Microconchid remains were recognized from the Zacler Beds (Westphalian) of the Nowa Ruda area in Lower Silesia. They were tentatively determined as? Microconchus sp. They have planispirally coiled tubes ranging in diameter from 0.9 to 2.5 mm. Some of the specimens are juveniles, while the rest are possibly mature. Well-visible ornamentation in the form of transverse thicker ribs and thinner longitudinal striae are present on the tube exterior of some well-preserved specimens. Microconchids occur on the surface of the leaf of the seed fern species Karinopteris daviesii.
EN
New tergite fragments of Arthropleura were found at the Nowa Ruda mine (Lower Silesia, Poland), after more than seventy years since any previous discovery. The small dimensions of the preserved structures, in terms of the genus Arthropleura, and the characteristic features of tuberculation probably indicate that the remains do not belong to the type species A. armata, but they could represent a new species. The occurrence of round protrusions in the broken-off tubercles is another feature of the new specimens, which has not been mentioned in the earlier literature. Unfortunately, the scanty remains that we have at our disposal (only two specimens were found) are not sufficient for the proposal of a new species. The number of valid Arthropleura species requires further investigation, especially regarding the features, which are diagnostic for species. The tergites described have very numerous tubercles, which may have taxonomic value in species discrimination. Because the fossils were found on a dump, their exact stratigraphic position is not known. However, they occur together with index leaflets of the seed ferns Paripteris gigantea and Linopteris sp., which enabled the age determination of Upper Namurian - Lower Westphalian for the fossils studied. This new discovery of Arthropleura contributes to a better understanding of the genus and of the Carboniferous land fauna of Poland, which is otherwise poorly known. This is also the first, detailed description of Arthropleura remains from the Polish Carboniferous.
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