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EN
Ophiuroids from the Upper Jurassic marine deposits (upper Oxfordian-lower Kimmeridgian) of southern and north-western Poland have been studied in two sections: Zalas quarry in the Kraków-Częstochowa Upland in southern Poland and Wapienno/Bielawy quarries in the Kuyavia region of north-western Poland. Described herein are nine taxa belonging to five genera (one new to science): Alternacantha Thuy and Meyer, 2013; Dermocoma Hess, 1964; Ophiobartia Loba gen. nov.; Ophioderma Müller and Troschel, 1840; Ophiotreta Verrill, 1899, and three families: Ophiacanthidae and Ophiodermatidae (both of Ljungman, 1867), and Ophiotomidae Paterson, 1985. Only a few representatives of some of these taxa have previously been reported from the Jurassic of Poland. One species, Ophiobartia radwanskii Loba, is established as new. The ophiuroid material recognized from both Polish localities is close to those described from Western Europe at family or even genus level. Both studied ophiuroid assemblages from Zalas and Wapienno/Bielawy show similarities, being dominated by the cosmopolitan species Ophioderma spectabile Hess, 1966, and by different species of Dermocoma. The recognized ophiuroid assemblages represent a rather shallow-water environment.
EN
Field work has resulted in the recognition of a previously unknown outcrop in the vicinity of the Zengővárkony lime-kilns (Mecsek Mountains, South Hungary) which has provided a remarkably rich, but poorly preserved, uppermost Oxfordian – earliest Kimmeridgian fauna dominated by ammonites probably representing the Hypselum–Bimammatum zones. This is the first description and illustration of Oxfordian–Kimmeridgian ammonites from the Mecsek Mountains. The cephalopod fauna comprises Phylloceras div. sp., Holcophylloceras div. sp., Sowerbyceras sp., Lytoceras sp., Lissoceratoides erato, Trimarginites cf. trimarginatus, Glochiceras (Coryceras) cf. microdomum, Subdiscosphinctes sp., ?Wegelea sp., Passendorferiinae gen. et sp. ind., ?Orthosphinctes sp., Euaspidoceras cf. radisense, Aspidoceras sp., A. cf. binodum, Physodoceras sp. ex gr. altenense-wolfi, Lamellaptychus sp., Laevaptychus sp. ex gr. hoplisus-obliquus. The fauna has a Mediterranean character (55% of Phylloceratidae and Lytoceratidae) and is similar to the Tethyan assemblages of the Venetian Alps (Italy), and Palma de Mallorca. The spirochaete tube worm Spiraserpula spirolinites is also the first record from the Mecsek Mountains. The Saccocoma wackestone-packstone microfacies is recorded with benthic foraminifera (Lenticulina sp. and Spirillina sp.) indicating well oxygenated and nutrient-rich bottom conditions.
EN
Radiolarian assemblages from the uppermost Oxfordian (Hypselum Zone) deposits of two sections (Katarowa Góra and Bobrowniki) in the Wieluń Upland (central Poland) are studied for the first time. The overall composition of the assemblages is characterized by low taxonomic diversity, with many individuals of spherical morphotypes, with dominance of the family Williriedellidae and Gongylothoracidae, among the nassellarians. The radiolarians show features mostly of the Northern Tethyan fauna. Additionally, more cosmopolitan forms consisting of spumellarians and of cold water representatives of the family Parvicingulidae appear in the middle and upper parts of the Hypselum Zone. This change in the character of the radiolarian assemblages suggests Boreal influences into the Submediterranean basin related to activity of sea currents, which have been stimulated by climatic changes during the latest Oxfordian.
EN
An extensive collection of ammonites made bed by bed from sections in the Submediterranean Upper Oxfordian of the Wieluń Upland, Central Poland, is described and used as a basis for a chronostratigraphical interpretation of the deposits. The ammonites are mostly of Submediterranean character and enable the recognition of the Bimammatum Zone, including the Bimammatum and Hauffianum subzones, as well as the lowermost Planula Zone distinguished here as a new biostratigraphical horizon – the matyjai horizon – based on the occurrence of Subnebrodites matyjai Wierzbowski et Głowniak sp. nov. The Submediterranean ammonites are mostly oppeliids with Taramelliceras (Taramelliceras) [M] – Glochiceras (Lingulaticeras) [m] the most numerous, as well as Taramelliceras (Richeiceras) and Taramelliceras (Metahaploceras) [M] – Glochiceras (Coryceras) [m]. The profusion of ammonites of these two groups in the stratigraphical interval studied provides new information on their evolution, and two new oppeliid species, Taramelliceras (Taramelliceras) zelcense Wierzbowski et Głowniak sp. nov. and Glochiceras (Lingulaticeras) bobrownikiense Wierzbowski et Głowniak sp. nov., are described here. Subboreal and Boreal ammonites are not common in these sections, but are nevertheless important for correlation. Subboreal ammonites of the family Aulacostephanidae are represented by the genus Vineta [M], including its newly recognized microconchiate counterpart, Vineta [m], and a newly established genus Vielunia [M] Wierzbowski et Głowniak gen. nov., with type species Vielunia dzalosinensis Wierzbowski et Głowniak sp. nov. The latter genus includes ammonites previously referred in the area of study to Ringsteadia, and with a microconchiate counterpart assigned to Prorasenia [m]. The Boreal ammonites comprise late cardioceratids assigned to Amoeboceras (Plasmatites). These ammonites indicate that the deposits in question from the Submediterranean Bimammatum Zone up to the Planula Zone correlate with the Subboreal and Boreal lowermost Kimmeridgian (Baylei Zone, and Bauhini Zone, respectively).
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