Geogaceta, 2022 Se presenta una nueva sección bioestratigrafica de la parte basal de la Formación Sueve. La nueva sección se suma a las nueve secciones descritas en estudios previos, relativos al sector septentrional del manto de Laviana.
Enrique Bernárdez +2 more
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The earliest cornulitid on the internal surface of the illaenid pygidium from the Middle Ordovician of Estonia [PDF]
Estonian Journal of Earth Sciences, 2017 The earliest cornulitid Cornulites sp. appears in the Darriwilian (Lasnamägi Regional Stage) of Estonia. Internal annulation is present in all Middle Ordovician cornulitids and could be a plesiomorphic character for the group.
Olev Vinn, Ursula Toom, Mare Isakar
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Permian trilobites and the applicability of the “living fossil” concept to extinct clades
Frontiers in Ecology and Evolution, 2023 Some taxa occupy our imaginations as “living fossils” because they were known from the fossil record before being discovered alive today. Other taxa are considered “living fossils” because modern relatives bear a strong morphological resemblance to ...
Melanie J. Hopkins +3 more
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Cruziana traces from the Late Silurian (Pridoli) carbonate shelf of Saaremaa, Estonia [PDF]
Estonian Journal of Earth Sciences, 2014 Late Pridoli Cruziana traces have recently been found in carbonate shelf sediments of the Ohesaare Formation on Saaremaa Island, Estonia. Cruziana isp. is interpreted here as a locomotory trace (repichnia) of an arthropod, possibly a trilobite.
Olev Vinn
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Preliminary report on the Oldenburg “butter shale” in the Upper Ordovician (Katian; Richmondian) Waynesville Formation, USA [PDF]
Estonian Journal of Earth Sciences, 2015 The Cincinnatian Series (Upper Ordovician; upper Katian) of the Cincinnati Arch region, Ohio, Indiana and Kentucky) contains several bed packages informally referred to as “butter shales” or “trilobite shales”.
Christopher D. Aucoin +3 more
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Early Silurian (Llandovery) Trilobite fauna from [PDF]
Journal of Sciences, Islamic Republic of Iran, 2020 The aim of this study is to analyze the assemblage of trilobites in the Silurian sequences of Iran by exploring stratigraphic section of the Silurian Niur Formation (Asadli section).
Hamed Ameri
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Abnormal trilobites from the Silurian and Devonian of Europe
Acta Palaeontologica PolonicaMalformed trilobites have been documented in deposits ranging from the Cambrian to the Permian. Continued examination of novel malformed specimens provides insight into how trilobites recovered from injuries, experienced genetic abnormalities, and ...
Russell D.C. Bicknell +3 more
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Why did the UV-A-induced photoluminescent blue–green glow in trilobite eyes and exoskeletons not cause problems for trilobites? [PDF]
PeerJ, 2015 The calcitic lenses in the eyes of Palaeozoic trilobites are unique in the animal kingdom, although the use of calcite would have conveyed great advantages for vision in aquatic systems.
Brigitte Schoenemann +2 more
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The making of pure quartzose sand in continental interiors: Paraná River (Brazil and Argentina)
Sedimentology, EarlyView.ABSTRACT As part of a comprehensive project on sedimentary processes in South America, this study focuses on sediment generation in the intracratonic Paraná Basin and monitors the evolution of sand composition along the Paraná River from central Brazil to the Río de la Plata estuary in Argentina.
Eduardo Garzanti +5 more
wiley +1 more source
Ancestral patterning of tergite formation in a centipede suggests derived mode of trunk segmentation in trilobites. [PDF]
PLoS ONE, 2012 Trilobites have a rich and abundant fossil record, but little is known about the intrinsic mechanisms that orchestrate their body organization. To date, there is disagreement regarding the correspondence, or lack thereof, of the segmental units that ...
Javier Ortega-Hernández, Carlo Brena
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