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EN
Sixty brachiopod species are reported from the Taboumakhlouf Formation (upper Eifelian) and the Bou Dib Formation (upper Eifelian to Givetian) of Jbel Issoumour, northern Maïder, Anti-Atlas, Morocco, on the basis of collections made by Volker Ebbighausen. The stratigraphy is based on reports of co-occurring trilobite assemblages. The relatively diversified fauna pre-dates the Taghanic event and is dominated in terms of diversity by atrypides and rhynchonellides (11 species each); other frequent species include Poloniproductus varians, Aulacella prisca, Tyersella tetragona, Schizophoria schnuri, Athyris ex gr. concentrica, Yeothyris? sinuata, and Thomasaria simplex. Spinatrypa ennigaldinannae Halamski and Baliński sp. nov. from the upper Eifelian is characterised by a transverse shell, typically 16–18 mm wide with 19–22 ribs. Prodavidsonia ebbigahuseni Halamski and Baliński sp. nov. differs from other representatives of the genus in having nearly flat shells. Eressella coronata Halamski and Baliński, nom. nov. is proposed as a replacement name for the permanently invalid Rhynchonella coronata Kayser, 1871 (non R. coronata Moore, 1861). Thomasaria simplex is documented as being a particularly variable species (costation, tongue, interarea position), so its broad taxonomic treatment is favoured. The brachiopod fauna shows distinct Rhenish affinities (numerous species in common with the Eifel and the Holy Cross Mountains) like the coeval fauna from southern Maïder, described previously. The Middle Devonian brachiopod fauna from the whole Maïder (north, described here and south, described previously) totals 87 species.
EN
Sparse fish microremains have been found in marine limestones from the Middle Devonian (Givetian) Skały Formation (Sitka Coral-Crinoid Limestone Member and Sierżawy Member), Świętomarz–Śniadka section, Bodzentyn Syncline, Łysogóry Region, northern Holy Cross Mountains, associated with conodonts of the hemiansatus to ansatus zones. Thelodont scales referred here to Australolepis sp. cf. A. seddoni come from near Śniadka village, from samples dated as hemiansatus to rhenanus/varcus zones. This increases the known range for the genus from its original find in Western Australia. The presence of a thelodont in the late Middle Devonian in Poland extends the known distribution of turiniids around the peri-Gondwana shorelines of Palaeotethys.
PL
W Górach Świętokrzyskich utwory terygeniczne środkowego żywetu są obecne tylko w regionie łysogórskim, gdzie w ­części wschodniej występują między iłowcami warstw skalskich a wapieniami biostromalnymi warstw pokrzywiańskich, natomiast w ­zachodniej – między iłowcami warstw skalskich i nieczulickich. Utwory te, należące do warstw świętomarskich, składają się z mułowców i piaskowców, a ich miąższość dochodzi do ok. 100 m. Pod względem składu piaskowce to drobnoziarniste arenity kwarcowe, wapniste arenity kwarcowe, rzadziej sublityczne, oraz waki kwarcowe i sublityczne, które mają podrzędny udział w laminowanych mułowcach ze szczątkami roślin. Podobny charakter petrograficzny mają równowiekowe piaskowce ogniwa żniatyńskiego z otworu wiertniczego Terebin IG 4 z połu­dniowo-wschodniej Lubelszczyzny. Źródłem materiału detrytycznego piaskowców warstw świętomarskich i ogniwa żniatyńskiego były reaktywowany orogen zbudowany ze skał silikoklastycznych oraz kratoniczna strefa bloku kontynentalnego. Do środkowodewońskiego basenu łysogórskiego materiał terygeniczny był dostarczany systemem deltowym z południowego wschodu. Środowiskiem sedymentacji warstw świętomarskich był obszar proksymalnej i dystalnej części prodelty progradującej w kierunku zachodnim.
EN
In the Holy Cross Mountains, Middle Givetian terrigenous deposits occur only in the Łysogóry region. In its eastern part they are found between claystones of the Skały Beds and biostromal limestones of the Pokrzywianka Beds, whereas in the western part - between claystones of the Skały Beds and the Nieczulice Beds. These deposits are ascribed to the Świętomarz Beds and consist of mudstones and sandstones reaching about 100 m in thickness. The sandstones encompass fine-grained quartz arenites, calcareous quartz arenites, rare sublithic arenites, quartz and sublithic wackes, being subordinate to laminated mudstones with plant remnants. The same petrographic characteristics are exhibited by the Żniatyń Member known from borehole Terebin IG 4 of the SE Lublin area. The source of detritic material for the Świętomarz Beds and the Żniatyn Member were recycled orogen built of siliciclastic rocks and a cratonic zone of the continental block. The terrigenous material was delivered to the Middle Devonian Łysogóry basin from the south-east through a deltaic system. The depositional environment was a proximal and distal area of prodelta that prograded to the west.
EN
Sixty-two Middle Devonian brachiopod species are described on the basis of >1300 specimens from the Taboumakhlof Formation (and subordinately probably also from the top of the El Otfal Formation) at Madne el Mrakib (middle to late Eifelian or early Givetian?), Aferdou el Mrakib (late Eifelian to middle Givetian), and Guelb el Maharch (early Givetian) on the southern edge of the MaÎder Syncline (eastern Anti-Atlas, Mo- rocco). Representatives of Craniida (2 taxa), Strophomenida (5), Productida (2), Orthotetida (2), Orthida (5), Pentamerida (5), Rhynchonellida (9), Atrypida (14), Athyridida (7), Spiriferida (9), and Spiriferinida (2) are present. The fauna is dominated quantitatively by the Atrypida (24% of taxa, about the half of specimens, and the commonest species Atryparia dispersa making up about 13% of the material); the Rhynchonellida (16% of taxa, about one-sixth of specimens) are the second largest order. A new genus of the family Pugnacidae (order Rhynchonellida), Paulinaerhynchia, is proposed with the type species P. paulinae gen. et sp. nov. from Maharch; it is closest to Pugnax, from which it differs in distinct costation, lack of a dorsal septum and septalium, and rudimentary dental plates. Desquamatia (D.) deserti sp. nov., a large and finely costate representative of the genus, is described also from Maharch. Antirhynchonella and Glosshypothyridina are reported for the first time or con- firmed to be present in the Givetian. Forty (possibly up to 46) species (71 or possibly up to 82% of the taxa identified at the species level) are present also in either Eifel (Germany) or the Holy Cross Mountains (Poland). Such a high ratio of species in common attests to unconstrained faunal exchanges among benthic faunas between the northern and southern shores of the Variscan Sea during the Middle Devonian. This favours the palaeogeo- graphic hypothesis of a narrow Variscan Sea.
EN
The continued investigations on the Middle Devonian part (Givetian, Middle through Upper Polygnathus varcus conodont Zones) of the section near the Renanue village in the Aragonian Pyrenees, Spain, brought twelve teeth of chondrichthyan taxa typical of the so-called "Omalodus shark assemblage" (Omalodus grabaui, Phoebodus fastigatus, Ph. sophiae, and probably Antarctilamna sp., the first record of Antarctilamna from the Givetian of Europe) previously known from a few places in Laurussia and North Gondwana. This taxonomic composition resembles the most that of the North Evans Limestone from New York. The species represent three different families and orders: Omalodontidae nov. (Omalodontiformes), Phoebodontidae (Phoebodontiformes), and Antarctilamnidae nov. (Antarctilamniformes nov.). In addition to the teeth of the listed taxa, several chondrichthyan scales of the "ctenacanth" type were found.
EN
Conodont faunas, mostly from previously unsampled sections of the Tafilalt (eastern Anti-Atlas, Morocco) and spanning the upper Givetian to basal Frasnian, include first records of species for the region and NW Gondwana as well as new taxa: "Ozarkodina" maroccanica n. sp., Polygnathus aequidivisus n. sp., Po. dengleri sagitta n. ssp., Po. jorfensis n. sp., Po. saevus n. sp., Po. tafilensis n. sp., and Schmidtognathus longicavus n. sp. The morphology of Tortodus subsymmetricus n. sp. suggests relation ships of Tortodus with Frasnian ancyrognathids. Other taxa are described in open nomenclature: Po. cristatus n. ssp., Icriodus aff. I. symmetricus, Skeletognathus aff. Sk. norrisi, and enigmatic supposed Pb elements (Gen. et sp. indet.). Ctenopolygnathus lanei Kuzmin (1995) is emended and distinctive morphotypes are recognized in Ct. angustidiscus and Po. collieri. Mesotaxis falsiovalis Sandberg et al. (1989) is a subjective junior synonym of the widely over looked M. guanwushanensis (Tian, 1988). There vised regional lithostratigraphy and conodont sequences allow to refine the upper Givetian zonation. The former Upper disparilis Zone is subdivided into succes sive Po. dengleri sagitta and Po. dengleri dengleri subzones. The basalmost Frasnian Ancyrodella rotundiloba pristina Zone (= MN 1 Zone) is preserved as a thin, condensed lime stone just at one locality (Bine Jebilet). The over lying Frasnes Event Beds (Lower Styliolinites) seem to fall in the subsequent Ad. rotundiloba soluta Zone (MN 2 Zone). Records of rare taxa, such as Po. paradecorosus, Po. Pollocki Morphotype 1, old est Po. webbi, Ct. angustidiscus, and Ct. lanei may be help ful for correlation into distant areas or shallower facies.
EN
The first occurrence of the conodont Ancyrodella rotundiloba has been used extensively for correlating the Middle-Up per Devonian (Givetian-Frasnian) boundary in sections worldwide despite many arguments as to its precise taxonomic definition. These arguments are summarised herein and three ontogenetic series illustrated from three samples across the Givetian-Frasnian boundary within the Vorota Formation of the Kozhym River section, Sub-Polar Urals, Russia. General trends within the three ontogenetic series suggest that the ratio of basal pit width to platform width in Ancyrodella pristina, and Ancyrodella recta in creases through ontogeny but the morphology of lateral secondary keel extensions to the basal pit remains constant and is a useful taxonomic feature. Folds and collars on the basal surface occur only in the later stages of development. The out line of the platform within species is variable and controlled by the formation of incipient nodes in juveniles; gerontic specimens can also have very variable platform out lines. Measure ments of platform width to basal pit width ratios and platform shape out lines may not therefore be a good way to compare between species. The three ontogenetic series provide typical late Givetian and early Frasnian examples and increase the potential for correlation of the Middle-Upper Devonian boundary particularly using juvenile Ancyrodella specimens.
EN
Detailed conodont data were obtained from 66 samples in 9 deep wells representative of three palaeogeographic regions of the Mid Devonian epicontinental basin of southeastern Poland: (1) the elevated part of the East European Platform representing the basin margin, (2) the Lublin Graben with a larger proportion of open marine systems, (3) the Radom Area characterized by more off shore, purely marine deposition and larger subsidence rates in the Radom Area. The 1344 specimens collected were as signed to 8 genera: Icriodus, Polygnathus, Ancyrodella, Belodella, Mehlina, Neopanderodus, Pandorinellina and Skeletognathus, and 38 taxa of species or subspecies rank. The vertical distribution of the conodont as semblages studied in particu ar sections is highly irregular and discontinuous with many barren intervals con rolled by less suitable palaeocological conditions, mostly representing restricted and/or very shallow-water facies. We found only a single index species characteristic of deeper marine facies, as applied in the standard conodont zonation. There -fore the biostratigraphic interpretation also takes into account the total range of all taxa found in particular samples, established after acritical analysis of adequately published total ranges of these taxa. The stratigraphicranges of the following taxa were modified: Icriodus arkonensis arkonensis, I. a. walliserianus, I. eslaensis, I. platyobliquimarginatus, I. subterminus, I. aff. I. subterminus, Polygnathus ansatus, P. latifossatus, P. linguiformis linguiformis, P. timorensis and P. varcus. As a result of the stratigraphic analysis of the conodon't assemblages we distin guished five zones in the Givetian of the studied area, i.e. the rhenanus/varcus, ansatus, hermanni, norrisi (=lower part of Lower falsiovalis Zone) zones, and also two in formal units, the subterminus and insita fau nas. We documented the co-occurrence of I. subterminus and P. latifossatus which supports the earlier supposition of Rogers (1998) that the Lower subterminus Fauna may partly corre pond to the Lower hermanni Zone.
EN
Stringocephalini gen. et sp. indet. A shows microscopic capillae on both valves, possibly representing a transitional evolutionary stage between smooth-shelled Stringocephalus and capillate Parastringocephalus. The latter genus seems therefore to have originated directly from Stringocephalus, and not via Subsinucephalus, as suggested earlier. The occurrence of Stringocephalini gen. et sp. indet. A indicates an early Givetian age of beds cropping out at Błonia Sierżawskie near Świętomarz.
EN
The conodont fauna and conodont-based biostratigraphy of a part of the Devonian succession of the Ściegnia section (Łysogóry region, Góry Świętokrzyskie Mountains [Holy Cross Mountains]) are discussed. The studied strata are composed of rhythmically bedded black shales and marly shales with intercalations of marly and coarse-grained limestones. They overlie the shales and sandstones of the Świętomarz beds. This part of the shale-marly succession of the Ściegnia section represents the lower part of Nieczulice beds of the Devonian informal lithostratigraphical scheme for the northern region of the Góry Świętokrzyskie Mountains. The conodont assemblages indicate that the studied sequence ranges from the upper part of the Lower varcus conodont Zone to the Middle varcus conodont Zone of the Givetian.
11
Content available remote Devonian rugose corals of the Phillipsastrea hennahii species group
EN
Massive phillipsastreid tetracorals similar to Phillipsastrea hennahii, defined as a Ph. hennahii species group, are characterized by reduced intercorallite walls (thamnasterioid or subthamnasterioid habit), by variable but generally good development of horseshoe dissepiments at the tabularium/dissepimentarium boundary, and by strongly deflected peripheral platforms at corallite margins. Seven species of the Ph. hennahii species group, mostly from the Givetian of southern Euramerica, Iberia and northern Gondwana, are reviewed. Two species, the Middle Givetian Phillipsastrea sobolewi (RÓŻKOWSKA 1956) and the Late Givetian Phillipsastrea jachowiczi, a new species described herein, both from the Holy Cross Mountains (Poland) are described and illustrated. Also described from that area is Phillipsastrea falsa COEN-AUBERT 1987 from the Upper Frasnian.
EN
The Givetian carbonate succession of the Mzurów 49-BN borehole, SW part of the Małopolska Massif, has been divided into three lithological units: set A (Amphipora limestones), set B (micritic limestones;subdivided into subsets B1 and B2), and set C (peritidal dolomites with evaporites). The sets represent three main depositional facies identified throughout the studied section. The succession corresponds to transgressive-regressive cycles identified in the Kielce region of the Holy Cross Mts., i.e. the northern part of Małopolska Massif. The event correlation is supported by biostratigraphy, based on conodonts and benthic faunas. These data indicate that the studied interval probably belongs to the latest part of the middle and late Givetian (Klaperina disparilis Zone to early Mesotaxis falsiovalis Zone). Set A represents largely shallow subtidal sediments deposited on an extensive shallow carbonate platform; its facies development shows many similarities to the youngest part of the Stringocephalus Beds and Dziewki Limestones. After a transgression in the late Givetian, open-marine micritic limestones (subset B1) were deposited. Their facies equivalent easily is readily identified as the Jaźwica Member in the southern part of the Holy Cross Mts. A regressive trend is recognized from the beginning of subset B2. Sea-level fall finally resulted in salinity increase in an isolated shallow-water basin of the Małopolska Massif. In mostly hypersaline conditions, cyclic deposition was developed. Three upward-shallowing metre-scale cycles within set C are recognised, each of them starting with thin calcareous mudstone beds with open marine biota and capped by grey dolomudstone with beds and nodules of gypsum or anhydrite.
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