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EN
Barnacle borings were found in six heterocoral skeletons. They are present as small (up to 2.9 mm long), slender, pouch-shaped borings with tapering, slit-like openings. The investigated borings were made by acrothoracican cirripedes, which mostly do not have a shell and bore into hard substrates to protect their “naked” bodies. The first occurrence of borings in skeletons of the heterocoral Oligophylloides Różkowska, 1969 from the Upper Devonian Tafilalt Platform was reported recently by Weyer in 2016. Here, the authors present the results of a detailed study of heterocoral remains with numerous acrothoracican borings from Jebel Bou Ifarherioun (Famennian, Anti-Atlas, Morocco). The borings were found on the basal part but also on broken branches and stems of the heterocoral corallum and occurred post mortem. There is no indication of a syn vivo coral-barnacle interaction with borings in tissue-covered areas. The authors used micro-CT scans to visualize the 3D morphology of the pits, their orientation, and distribution. Additionally, the 3D morphology of an assemblage of 75 pits was used to carry out ordination and cluster analyses, which showed that previously proposed ichnospecies may be a continuum of morphological variability. In the basis of measurements by the present authors, the studied borings do not fit any known ichnotaxa. The absence of bourrelets excludes the possibility that the borings studied belong to the ichnogenus Rogerella Saint-Seine, 1951. Hence, the results seem to contradict a synonymization that was proposed by Bromley and D’Alessandro (1987) and subsequent authors and leave room for further research and discussion on this topic. Although the inferred boring organism is a filter feeder and, thus, depends on currents, the authors did not find a preferential orientation of the borings. The samples considered here are the best-preserved Devonian barnacle borings to date.
EN
The Shotori Range of east-central Iran (east of Tabas) has yielded Famennian ammonoid assemblages dominated by the family Sporadoceratidae. Four genera Maeneceras Hyatt, 1884, Iranoceras Walliser, 1966, Sporadoceras Hyatt, 1884 and Erfoudites Korn, 1999 are represented. The conodont assemblage of one sample containing Iranoceras revealed an Upper marginifera Zone age. The ammonoid assemblages are characterised by comparatively large specimens; they reach conch diameters of 300 mm (including the body chamber) and the mean size is larger than 100 mm. The preservation of the material from the Shotori Range and size comparison with sporadoceratid assemblages from the Anti-Atlas of Morocco and the Rhenish Mountains of Germany suggest that hydraulic sorting has resulted in a bias towards large conchs, explaining the size distribution, rather than latitudinal differences. The new species Maeneceras tabasense is described; the genus Iranoceras is revised with a new description of the two species Iranoceras pachydiscus (Walliser, 1966) and Iranoceras pingue (Walliser, 1966).
3
Content available remote Geochronology of granitoids from Psunj and Papuk Mts., Croatia
EN
Detailed cathodoluminescence (CL) and back scattered electron (BSE) imaging of zircon crystals, coupled with in-situ U-Pb zircon dating by Laser Ablation Multi-Collector Inductively Coupled Plasma Mass Spectrometry (LA-MC-ICP-MS) were used to develop new insights into the evolution of a monzogranite from Omanovac Quarry (Psunj Mt.), and of monzogranites from Šandrovac Quarry and Kišeljevac Creek (Papuk Mt.), both located in the Slavonian Mountains (Croatia). U-Pb isotopic data yielded a concordia age of 380 ± 4 Ma for the monzogranite from Omanovac Quarry, and 382 ± 2 Ma and 383 ± 5 Ma for monzogranites from Šandrovac Quarry and Kišeljevac Creek. The results suggest Late Devonian magmatic activity.
EN
Samples from the Upper Frasnian (Devonian) of Lompret Quarry and Nismes railway section in Dinant Synclinorium, southern Belgium, yielded several chondrichthyan teeth and scales. The teeth belong to three genera: Phoebodus, Cladodoides and Protacrodus. The comparison with selected Late Frasnian chondrichthyan assemblages from the seas between Laurussia and Gondwana revealed substantial local differences of taxonomic composition due to palaeoenvironmental conditions, such as depth, distance to submarine platforms, oxygenation of water, and possibly also temperature. The assemblage from Belgium, with its high frequency of phoebodonts, is the most similar to that from the Ryauzyak section, South Urals, Russia, and the Horse Spring section, Canning Basin, Australia.
EN
Late Devonian coarse-grained carbonate deposits in the Holy Cross Mountains were studied for possible storm depositional systems and catastrophic tsunami events, as it must be assumed that the investigated area was strongly affected by tropical hurricanes generated in the open ocean North of Gondwana. This assumption appears consistent with diagnostic features of carbonate tempestites at several places in the Holy Cross Mountains. Sedimentary structures and textures that indicate so are, among other evidence, erosional bases with sole marks, graded units, intra- and bioclasts, different laminations and burrowing at the tops of tempestite layers. It has been suggested before that a tsunami occurred during the Late Devonian, but the Laurussian shelf had an extensional regime at the time, which excludes intensive seismic activity. The shelf environment also excluded the generation of tsunami waves because the depth was too shallow. Additionally, the Holy Cross Mountains region was surrounded in the Devonian by shallow-marine and stable elevated areas: the Nida Platform, the Opatkowice Platform and the Cracow Platform to the South, and the elevated Lublin-Lviv area to the NE. Thus, tsunami energy should have been absorbed by these regions if tsunamites would have occurred.
EN
Interregional tracing of trends and events in the biotic evolution is an important task of modern palaeobiology. In Soviet times (1917-1991), numerous palaeontological data have collected for the territory of Russia and neighbouring U.S.S.R. countries. Later, these data were compiled and published in a series of reference volumes. Although this information cannot be updated in a conventional way, it remains valuable for quantitative analyses, particularly because of its comprehensive and unique character. Assessment of the previously collected data on the stratigraphic distribution of Middle Devonian-Mississippian marine invertebrates in three regions of central Asia (central Kazakhstan, Uzbekistan and Tajikistan) reveals some general patterns of biodiversity dynamics. The total number of genera generally declined during the Givetian-Famennian, whereas a remarkable diversity peak occurred in the Visean. This is consistent with the global pattern and, thus, permits to hypothesize a regional signature of the global trends. Changes in the extinction rate differ, however, between central Asia and the Earth in its entirety, which may be explained particularly by biases in either the regional or the global records. Evidence of the Givetian and Frasnian/Famennian mass extinctions is found in the three regions under study. Results of this tentative study indicate important directions for further research and suggest that central Asia is a highly important domain for studies of mid-Palaeozoic biodiversity dynamics.
EN
The Albergaria-a-Velha Unit is one of several tectonostratigraphic out-of-sequence units of the metamorphic belt associated with the Porto-Tomar shear zone (Ossa-Morena Zone, W Portugal). It is composed of considerably deformed - very low grade - metasediments, namely shales, siltstones and rare fine sandstones. In this work we present new sedimentological and biostratigraphical data that suggest the Albergaria-a-Velha Unit was deposited from the (?)early Frasnian to the Serpukhovian in a distal marine environment, where turbiditic and basinal sedimentation prevailed. Palynofacies analysis and lithological data point to a gradual increase of terrestrial input, suggesting a prograding system. Detrital framework data is indicative of a stable cratonic sediment source area composed of low grade metamorphic rocks. The timing of the onset of the Porto-Tomar shear zone activity and consequently its influence on the sedimentation of this unit is discussed. Organic petrology and geochemistry data indicate that the Albergaria-a-Velha Unit is within the dry gas window in terms of hydrocarbon generation ranges.
EN
Five species of the Late Famennian family Balviinae korn 2002, Effenbergia lens korn, 1992, E. minutula korn, 1992, Kenseyoceras nucleus (schmidt, 1924), K. biforme (schindewolf, 1937), and Balvia globularis (schmidt, 1924), are described from the Holy Cross Mountains, Central Poland. The material comes from the "Wocklumeria Beds" of the kowala, ostrówka and Besówka sections, possibly from the Effenbergia lens - Parawocklumeria paradoxa zones and from the upper part of the Wocklumeria sphaeroides Zone - Epiwocklumeria applanata subzone of the Late Famennian.
EN
Ongoing magnetostratigraphic and geochemical studies (including major and trace element geochemistry and stable isotopes of C, N, O) in the Canadian Rocky Mountains are providing insight into the paleoenvironmental changes of the mid-Frasnian punctata Event, a prominent marine geochemical perturbation. The data is evaluated with 1) a regional sequence stratigraphic perspective and 2) within the context of a rapidly changing Late Devonian world, characterized by numerous sedimentological and faunal perturbations leading up to the eventual Frasnian-Fammenian (F/F) mass extinction. Proxies for bottom water paleoredox conditions (Mo, V, U), oceanic primary productivity (δ13Corg, δ15Nbulku, Cu, Ni, Ba), changes in detrital input (Si, Al, K, Ti, Zr), and magnetic susceptibility display similar trends, indicating that these proxies and MS variations are inherently linked. The observed excursions suggest that changes in detrital input were the main driver of a bioproductivity increase. Elevated organic matter export from the photic zone likely led to the deposition and later preservation of organic-carbon rich facies under facilitated conditions of bottom water suboxia-anoxia. These geochemical trends were likely influenced by eustatic sea level change, but may have been enhanced by pulses of coincident orogenic activity and pulses of terrestrial afforestation. The rise and expansion of the first true forests is thought to have drastically altered nutrient fluxes to the oceans via increases in pedogenesis and the expansion of a mature soil profile. Our work is intended to complement the growing body of research aimed at elucidating the causes and understanding the effects of terrestrial and marine events of the P. punctata biozone and, more broadly, at understanding the Earth-system changes of the Late Devonian leading up to the F/F boundary.
EN
Nine bryozoan species are described from the Jurginskaya Formation (Famennian, Late Devonian) from Western Siberia, Russia, namely: Leptotrypella pojarkovi Orlovski, 1961, Rhombopora subtilis Nekhoroshev, 1977, Klaucena lalolamina Yang, Hu, Xia, 1988, Eofistulotrypa famennensis sp. n., Atactotoechus cellatus sp. n., Nikiforopora jurgensis sp. n., Eridotrypella tyzhnovi sp. n., Mediapora elegans sp. n., and Klaucena gracilis sp. n. The studied assemblage shows palaeogeographical affinity with Kazakhstan, Kirgizia, Transcaucasia, China, and the United States of America.
EN
The Frasnian-Famennian (F-F) boundary in Central Iran has been investigated on the basis of conodont faunas (34 species and subspecies) from four sections: Chahriseh near Esfahan, and Kal-e-Sardar, Howz-e-Dorah and Ghale-Kalaghu near Tabas. The F-F boundary in the Chahriseh section is located in a one-metre interval between beds EX1 and F-F9 whereas in the Kal-e-Sardar section it is at the base of bed Cly1. The F-F boundary can not be recognized in the Howz-e-Dorah and Ghale-Kalaghu sections be cause of uncon form able relation ships and erosion of the upper most late Frasnian beds indicated incidentally by reworked boulders (indicating con temporaneous tectonic activity) and by the abrupt appearance of contrasting environments, including tempestites at the base of the lower Famennian. The best conodont and palaeoenvironmental data were obtained from the Kal-e-Sardar section where a deeper marine environment prevailed during the late Frasnian, be coming shallower in the early Famennian; the Chahriseh section displays small fluctuations in sea level during the early Famennian. The conodont faunas display the inception of the Polygnathus communis group in the late Frasnian (rhenana-linguiformis zones) and the appearance of Icriodus alternatus mawsonae in the Late rhenana Zone. A new age-range is suggested for Polygnathus aequalis Klapper and Lane, from the transitans to the linguiformis zones. Three conodont biozones are represented in the late Frasnian to early Famennian of the Chahriseh section, two late Frasnian and one early Famennian in the Kal-e-Sardar section and two biozones in the late Frasnian and early Famennian of both the Howz-e-Dorah and Ghale-Kalaghu sections. Two new species are described: Polygnathus tabasianus (Early to Late crepida zones) and Polygnathus vachiki (Late rhenana-linguiformis zones).
EN
Coelacanth fishes from the Upper Devonian of the Holy Cross Mountains, Poland, are described. The material consists of isolated incomplete lower jaws, gular plates, an entopterygoid and urohyal. The isolated lower jaws belong to Diplocercides kayseri (VON KOENEN, 1895). The other coelacanth remains are referred to Diplocercides sp. indet. All specimens are Famennian in age (Early Palmatolepis rhomboidea conodont Zone), representing a time when almost all of the Holy Cross Mountains carbonate platform was drowned. Because of the shallow-water living conditions preferred by the group it is assumed that these coelacanths were restricted to isolated, small submarine swells, which still existed in that region in the latest Devonian, and that their carcasses were then subjected to post-mortem transport into the deeper areas.
EN
Main Late Devonian placoderm taxa known from the Holy Cross Mountains are characterised. The distribution of the Late Devonian placoderm fossils is described. Variation in their occurrences depend on the sedimentation environment of the rocks which contain fossils of this group. Connections between the Holy Cross Mountains placoderms development and the synsedimentary tectonic processes active in this area during the Late Devonian is discussed, and the local faunas compared to classic assemblages of the same age from Latvia.
14
EN
The taxonomic description of the Late Devonian and Early Carboniferous Rugosa from the boundary area of the Precambrian East European Craton and the Palaeozoic platform of Central Europe is presented. Palaeontological analysis and the stratigraphical distribution of the corals in Western Pomerania enabled recognition of several faunistic events, which reflect evolutionary trends in rugose corals. The pre-crisis Frasnian coral fauna, dominated by colonial forms, both massive [Disphyllia laxa] (GÜRICH, 1896), [Hexagonaria hexagona kowalae] (WRZOŁEK, 1992), ?Frechastraea] and branching [Disphyllum kweihsiense YOH, 1937,Peneckiella ?fascicularis (SOSHKINA, 1952), [Thamnophyllum monozonatum] (SOSHKINA, 1939), [Peneckiella szulczewskii] (RÓŻKOWSKA, 1979), developed on the carbonate platform extending along the edge of the East European Craton. The similarity of these faunas to Rugosan faunas from southern Poland is significant. The coral fauna was reduced significantly after the Kellwasser crisis. Colonial corals disappeared altogether and solitary dissepimented forms were markedly reduced. The subsequent Late Famennian radiation caused a significant quantitative and qualitative differentiation of the coral faunas. In addition to the well-known "Cyathaxonia fauna", warm and shallow-water solitary corals appeared in the latest Famennian. The stratigraphically important taxa of the latest Famennian include: [Campophyllum] (MILNE-EDWARDS & HAIM, 1850), [Palaeosmilia aquisgranense] (FRECH, 1885), [Bounophyllum pomeranicum sp. nov.] and [Guerichiphyllum kowalense] (RÓŻKOWSKA, 1969). The latest Famennian regression caused subdivision of the Pomeranian area into at least two sedimentary basins, separated by shallows, with peculiar ecological conditions, and the appearance of numerous endemic taxa. This regressive interval contains, however, numerous levels yielding less restricted faunas, which suggest the intermittent appearance of more open-sea conditions.
15
EN
New records of the triangularly coiled Soliclymenia paradoxa (MUNSTER, 1839) from Dzikowiec (Sudetes, Poland) allow the study of intraspecific variability. It can be demonstrated that at least three species within the genus Soliclymenia can be separated. The genus has a limited stratigraphic distribution within the .Wocklumeria Stufe. of the Late Devonian, but a wide geographic range within the tropical seas.
EN
The mid-Late Devonian pelagic sedimentary successions of the Rhenish Mountains and other regions show a double black shale horizon called the annulata Black Shale. It marks, at the species level, a prominent faunal turnover of ammonoids from the Prolobites delphinus Zone into the Platyclymenia annulata Zone. An analysis of ammonoid genera distribution, phylogenetic relationships, andmorphospace occupation demonstrates that the "annulata Event" does not correspond to a crisis of the group and does not fulfill the criteria of a major biotic event.
17
EN
On the western slope of the Southern Urals, a continuous conodont zone sequence within different facies of the Frasnian-Famennian (F-F) boundary beds is documented. In all the sections the boundary between both stages runs within lithologically uniform successions and can be determined only by a sharp faunal change. In brachiopod facies, it is placed within brachiopod shell beds and relates to the base of the Barma Beds, i.e., the level marked by a simultaneous appearance of the index brachiopod species Pugnoides(?) markovskii and the zonal conodont species Palmatolepis triangularis. In goniatite facies, the F-F boundary can be traced by the disappearance of diverse Frasnian conodonts and goniatites of the genus Manticoceras, coupled with the first occurrence of the conodont Pa. triangularis; the sequence shows also the well-known icriodid blooms in the earliest Famennian. Finds of Famennian goniatites (representatives of the genus Cheiloceras) are confined to the crepida zones. In the sections of theWest-Zilair, where the F-F boundary passage consists of siliceous- terrigenous deposits, the boundary can be established only by a change in conodont assemblages. In all the sections under investigation the F-F boundary level shows a drastic faunal change that corresponds to the global Kellwasser Event.
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