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The xiphosurans Bellinurus lunatus (Martin, 1809) and Euproops rotundatus (Prestwich, 1840) are described from sideritic concretions hosted by the Orzesze Beds (Westphalian B) in. the Polish region of the Upper Silesia Coal Basin. Associated flora and fauna include terrestrial plant remains and a single palaeodictyopteran insect nymph. As no marine influences are known in this area since the Namurian A, these xiphosurans were probably fresh-water organisms.
Organic remains of tentaculitids have been recovered during palynological research on archival samples from the Dobrzyca 2 borehole (Western Pomerania). Until now tentaculitids are widely known from their abundant mineralised shells. As organic remains, on the other hand, they have only been known since 2004. The present discovery is currently the second one of this kind found in Upper Devonian strata. The shape and morphology of some recognized tentaculitid organic remains are similar to embryonic and juvenile forms of dacryoconarids belonging to orders Nowakiida and Stylionida. Based on palynomorphs, the age of the two samples investigated has been established as Frasnian, RB and RD local miospore zones.
Investigation of mixed carbonate−siliciclastic Lower Devonian deposits have been carried out in the Ivanye Zolote and Ustechko sections in Podolia, Ukraine. Based on palynomorph evidence, the age of the samples studied is late Lochkovian, not older than the NM Oppel Miospore Zone, specifically the Si Lineage Zone. The presence of acritarchs and chitinozoans points to dominantly marine depositional conditions. However, a regressive environmental change toward more brackish conditions is indicated by a decrease in the taxonomic diversity of acritarchs in the topmost samples, the simultaneous disappearance of chitinozoans, and an increase in leiosphaerid frequency. Furthermore, evolution of limestone microfacies demonstrates a progressive transition from a shrinking marine basin toward a brackish, storm−affected muddy lagoon, manifested by recurrent profusion of impoverished, mostly opportunistic and euryhaline shelly benthos (nuculanid bivalves, leperditicopids and other ostracods, terebratulid brachiopods), chaetetid demosponges and diverse ichthyofauna. The association of plant (mainly nematophytes and some tracheids) and animal (eurypterid, ?scorpion, and possibly other arthropod) remains points to the presence of nearby Early Devonian wetland vegetation, providing food and shelter for various semi−aquatic and other terrestrial arthropods.
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