13 research outputs found

    OCURRENCE OF LINGULAPHOLIS (CRANIOPSIDAE, BRACHIOPODA) IN THE PIMENTEIRA FORMATION (DEVONIAN, PARNAÍBA BASIN): Registro de Lingulapholis (Craniopsidae, Brachiopoda) na Formação Pimenteira (Devoniano, Bacia de Parnaíba)

    Get PDF
    The genus Lingulapholis had temporal and spatial restrictions during the Devonian, being found only in Colombia and the United States. In Brazil, its related taxa Craniops is common in the Amazonas, Paraná, and Parnaíba basins. New data from the cities of Picos and Itainópolis, east flank of Parnaíba Basin, led to the discovery of a yet previously undescribed brachiopod genus for this region of Gondwana. The Lingulapholis brachiopod was found associated with plant fragments under conditions of moderate to low hydrodynamic energy as indicated by ichnological assemblage, in proximal expressions of Cruziana ichnofacies alternated to Skolithos ichnofacies. The presence of Lingulapholis suggests that the Parnaíba Basin was inserted in the zone of diffuse faunal mixing during the Middle Devonian.ABSTRACT - The genus Lingulapholis had temporal and spatial restrictions during the Devonian, being found only in Colombia and the United States. In Brazil, its related taxa Craniops is common in the Amazonas, Paraná, and Parnaíba basins. New data from the cities of Picos and Itainópolis, east flank of Parnaíba Basin, led to the discovery of a yet previously undescribed brachiopod genus for this region of Gondwana. The Lingulapholis brachiopod was found associated with plant fragments under conditions of moderate to low hydrodynamic energy as indicated by ichnological assemblage, in proximal expressions of Cruziana ichnofacies alternated to Skolithos ichnofacies. The presence of Lingulapholis suggests that the Parnaíba Basin was inserted in the zone of diffuse faunal mixing during the Middle Devonian. RESUMO - - O gênero Lingulapholis teve restrições temporais e espaciais durante o Devoniano, sendo encontrado apenas na Colômbia e nos Estados Unidos. No Brasil, seu táxon relacionado Craniops é comum nas bacias do Amazonas, Paraná e Parnaíba. Novos dados das cidades de Picos e Itainópolis, flanco leste da Bacia do Parnaíba, levaram à descoberta de um gênero de braquiópode ainda não descrito para esta região do Gondwana. O braquiópode Lingulapholis foi encontrado associado a fragmentos de plantas em condições de moderada a baixa energia hidrodinâmica, conforme indicado pela assembleia icnológica, em expressões próximas de icnofácies Cruziana alternadas a icnofácies Skolithos. A presença de Lingulapholis sugere que a Bacia do Parnaíba esteve inserida na zona de mistura faunística difusa durante o Devoniano Médio

    Tafofácies, correlação estratigráfica e paleoambientes em uma nova seção Devoniana na Bacia do Paraná (PR, Brasil). e2322740

    No full text
    The stratigraphic framework in the southern portion of the Paraná Basin, represented by the Devonian System strata, preserves a rich fossil deposit. This deposit is marked by the presence of a paleofauna commonly referred to as endemic, composed of benthicorganisms from the Malvinocaffric Realm. The present study constitutes the interpretation of a new depositional section, and for this purpose, the new areas were visited in the field and described in terms of facies, ichnology, and taphonomy. The research resulted in the interpretation of facies from a marine environment influenced by storms in a situation of ecological stress established immediately before the Kačák extinction even

    Paleoenvironments of a regressive Devonian section from Paraná Basin (Mato Grosso do Sul state) by integration of ichnologic, taphonomic and sedimentologic analyses

    No full text
    ABSTRACT: Studies that integrate ichnologic, taphonomic and sedimentologic data result in more accurate paleoenvironmental inferences than isolated approaches. Most of paleontological studies regarding Devonian from Paraná Basin were conducted in the southern part of the basin (Paraná state), precluding taphonomic or ichnologic studies to the northern part, and even its macrofossils content is understudied. This study analyzes paleoecologic and depositional conditions represented by trace fossils, macrofossils and sedimentary facies in a regressive Devonian section from Paraná Basin, Mato Grosso do Sul state, Brazil. Seven ichnofabrics (Macaronichnus, Psammichnites, Arenicolites-Skolithos, Cylindrichnus-Skolithos, Zoophycos, Rhizocorallium-Palaeophycus, and Chondrites ichnofabrics) and three taphofacies (T1: parautochthonous to allochthonous preservation; T2: Autochthonous preservation; and T3: time-averaged autochthonous to allochthonous association) were diagnosed. The studied sections are positioned in a highstand systems tract (HST) exhibiting dominance of sandy facies, and four sub-environments were defined: foreshore; shoreface; storm-dominated shoreface to transitional offshore; and offshore. The dominance of foreshore to shoreface settings in a HST corroborates a shallower context in relation to the southern part. However, similarities in the facies and ichnofacies stacking, as well in the macrofossil content suggest that the hypothetical division between two sub-basins (Apucarana and Alto Garças Sub-basins) was not complete until early Emsian

    Devonian agglutinated polychaete tubes: all in all it's just another grain in the wall

    No full text
    International audienceBiomineralized and organic metazoan tubular skeletons are by far the most common in the fossil record. However, several groups of organisms are also able to agglutinate particles to construct more rigid structures. Here we present a novel type of agglutinated tube from the austral and endemic palaeobiota of the Malvinokaffric realm (Devonian, Brazil). This fossil is characterized by an agglutinated tube made of silt-sized particles forming an unusual flanged morphology that is not known from the fossil record. Besides being able to select specific particles, these organisms probably lived partially buried and were detritus/suspension feeders. Comparisons across different modern groups show that these fossils are strongly similar to tubes made by polychaetes, specifically from the family Maldanidae. If this interpretation is correct, then an early divergence of the Sedentaria clade may have occurred before the Devonian
    corecore