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Number of results: 10
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Abstract

An early Permian (late Artinskian–Roadian) cladid crinoid (Catacrinidae gen. et sp. indet.) is reported for the first time from the V ø ringen Member of the Kapp Starostin Formation of Spitsbergen. The specimen is partly articulated and preserves a considerable part of its stalk and a complete cup, but only the proximal portions of its arms. Thus, it cannot be identified with any degree of certainty at the generic level. Despite this, our finding is important as it constitutes one of the youngest records of catacrinid crinoids to date and considerably extends the palaeogeographic distribution of this group.
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Abstract

Starostinella nordica gen. et sp. n. is described from the uppermost Permian (Kapp Starostin Formation) of the Kapp Starostin (Isfjorden) in West Spitsbergen. The new genus is attributed to Trachypsammiidae Gerth - a family incertae sedis among Cnidaria. Members of the Trachypsammiidae have been previously associated with different higher rank taxa within the Cnidaria, or their skeletons were interpreted as a result of symbiosis of a cladochonoidal organism (Tabulata) with an indeterminate hydroid or stromatoporoid. S. nordica gen. et sp. n. seems to support the latter assumption. Hydrocoralla of S. nordica have a simpler structure than those of other Trachypsammiidae and are branching like those of Cladochonus. Their thick-walled, horn-shaped hydrocorallites are surrounded with a very thick cortical zone of sclerenchyme organized into trabecular microstructure. The proper corallite wall is fibro-radial in structure, sharply distinct from the outer cortical zone.
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Abstract

The ostracod fauna were examined from the Kapp Starostin Formation sequences (Upper Permian) from West Spitsbergen (Svalbard). The ostracod taxa are mainly confined to 3 superfamilies: Kirkbyacea, Healdiacea and Bairdiacea. 11 taxa are identified. One new species, Kindlella bellsundi is proposed. The ostracod assemblage dominated by kirkbyacean taxa is related to open shelf marine environment.
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Abstract

The fusulinid foraminifers of Schellwienia arctica (Schellwien, 1908) have been investigated from Polakkfjellet Mt., south Spitsbergen, and used as biostratigraphic marker for the latest Carboniferous earliest Permian strata of the Treskelodden Formation. A series of thin sections enable to investigate the internal structure and growth pattern of individual specimens. The observed variation of growth suggests dynamic environmental conditions at the investigated location and most likely over one-year long life span of this foraminifer.
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Abstract

An unusual 6–8 cm layer of prismatic cartilage and matrix containing some 8,800 teeth, coprolites, incomplete occipital spines, and denticles of Orthacanthus platypternus (Cope, 1883) occurs in the lower Permian (Artinskian) Craddock Bonebed in Texas, USA. It is the only species of shark present in the Clear Fork Group except for three worn Xenacanthus Beyrich, 1848 occipital spine fragments and two teeth of ?Lissodus (Polyacrodus) zideki (Johnson, 1981) (Hybodontoidei), both being the first occurrences in this unit. Analysis of measurements of teeth with complete bases randomly selected from 3,050 initially available teeth failed to reveal the presence of sexual dimorphism or the discrete presence of juveniles as expected, based on an independent study which identified the presence of Orthacanthus juvenile occipital spines. A few highly symmetrical small teeth are present, which had not been previously observed in the Texas lower Permian. They may be symphyseals and restricted only to juveniles. Other unusual teeth include germinal teeth and deformed teeth, both of which occur in the Clear Fork and underlying Wichita groups. One tooth displays an apparent example of the equivalent of an “enamel pearl” on one of its cusps. The most unusual teeth are those that appear to have undergone various stages of resorption. Only the lingual margin of the base is affected in which the apical button is resorbed to varying degrees until only the labial margin with the basal tubercle and the three cusps are all that remain. If the teeth were undergoing resorption, then the perplexing problem is why the apical button is resorbed and not the superjacent basal tubercle. Other vertebrate remains include palaeoniscoid scales and teeth and unidentified tetrapod bone fragments, jaw fragments, and teeth. Rare fragments of bones (scales?) bear a “comb edge” which have not been previously observed in the Texas lower Permian.
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Abstract

Productacean brachiopod assemblages are described from 10 taphocoenoses from various facies of the Upper Permian Kapp Starostin Formation in Spitsbergen. Time and space relationships among the investigated phena are based upon a previously established chronostratigraphic correlation of the strata. 15 productacean species are distinguished, based upon analysis of their morphology and ecology. Their paleontological descriptions take into account the ranges of their ecophenotypic variation. Shells adapted to three modes of life are recognized among the considered Productacea: (1) forms stabilizing within loose bottom sediments, (2) forms floating at the surface of soft substrates, and (3) forms living just below the surface of quaggy substrates. Distribution of the productacean assemblages in the Kapp Starostin Formation is analyzed within the framework of a reconstruction of the history of the Permian sea in this area. The main ecological controls upon this distribution include stratification of the water, substrate suitability for settlement, and coastal influences on the marine environment. Because of their spatially limited distribution and unrecognized evolution within the considered time interval, the investigated brachiopods cannot be employed for biochronostratigraphy.
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Abstract

New coral taxa Tetraporinus siedlecka sp. n. and Roemeripora aspinosa major ssp. n. are erected from the Lower Permian (Sakmarian and Artinskian) Treskelodden Formation of Hornsund area, Spitsbergen and Syringopora sp. similar to S. subreticulata Nowiński, 1991 are described. Studies on stable isotope ratios of carbon and oxygen in the skeletons of tabulate and rugose corals from Hyrnefjellet and Treskelen areas show that these organism did not frac­tion the isotopes to much. The differences in isotope fractionation, both for carbon and oxygen, reached 2 ‰ comparable to the concurring brachiopods, accepted as reference level.
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Abstract

Campyloprion Eastman, 1902 is a chondrichthyan having an arched symphyseal tooth whorl similar to that of Helicoprion Karpinsky, 1899, but less tightly coiled. The holotype of Campyloprion annectans Eastman, 1902, the type species of Campyloprion, is of unknown provenance, but is presumed to be from the Pennsylvanian of North America. Campyloprion ivanovi (Karpinsky, 1922) has been described from the Gzhelian of Russia. A partial symphyseal tooth whorl, designated as Campyloprion cf. C. ivanovi, is reported from the Missourian Tinajas Member of the Atrasado Formation of Socorro County, New Mexico, USA. Partial tooth whorls from the Virgilian Finis Shale and Jacksboro Limestone Members of the Graham Formation of northern Texas, USA, are designated as Campyloprion sp. Two partial tooth whorls from the Gzhelian of Russia that were previously referred to C. ivanovi are designated as Campyloprion cf. C. annectans. The age of Toxoprion lecontei (Dean, 1898), from Nevada, USA, is corrected from the Carboniferous to the early Permian. An alternative interpretation of the holotype of T. lecontei is presented, resulting in a reversal of its anterior-to-posterior orientation. The genera Helicoprion, Campyloprion, and Shaktauites Tchuvashov, 2001 can be distinguished by their different spiral angles.
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Abstract

Stable isotopes 18O and 13C record of the Kapp Starostin Formation (Late Permian) is presented. The interdependence of δ18O nad δ13C isotope time series is applied for calculating paleotemperatures in the depositional basin of the Kapp Starostin Formation. The obtained results indicate overall cooling from c. 25°—10°C, and confirm some paleogeographical and paleoclimatical inferrences.
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Abstract

The Panorama Point Beds represent a subfacies of the Early to Middle Permian Radok Conglomerate, which is the oldest known sedimentary unit in the Prince Charles Mountains, MacRobertson Land, East Antarctica. This unit records clastic sedimentation in fresh−water depositional system during the early stages of development of the Lambert Graben, a major structural valley surrounded by crystalline highlands in the southern part of Gondwana. It contains common siderite precipitated through early diagenetic processes in the swamp, stagnant water, and stream−flow environments. There are two types of siderite in the Panorama Point Beds: (1) disseminated cement that occurs throughout the sedimentary suc− cession; and (2) concretions that occur at recurrent horizons in fine−grained sediments. The cement is composed of Fe−depleted siderite (less than 90mol%FeCO3)with an elevated con− tent of magnesium, and trace and rare earth elements. It has negative #2;13CVPDB values (−4.5 to −1.5‰). The concretions are dominated by Fe−rich siderite (more than 90mol% FeCO3),with positive 13CVPDB values (+1 to +8‰). There are no noticeable differences in the oxygen (18OVPDB between −20 and −15‰) and strontium (87Sr/86Sr between 0.7271 and 0.7281) iso− topic compositions between the siderite types. The cement and concretions developed in the nearsurface to subsurface environment dominated by suboxic and anoxic methanic degrada− tion of organic matter, respectively. The common presence of siderite in the Panorama Point Beds suggests that fresh−water environments of the Lambert Graben were covered by vegetation, starting from the early history of its development in the Early Permian.
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