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Los restos de asterozoos son sumamente escasos en el Ordovícico Medio y Superior del suroeste de Europa, si bien la auténtica diversidad de estos equinodermos está largamente enmascarada por su dificultad de fosilización. En este trabajo se presenta la segunda localidad centroibérica donde se registra el ofiuroideo Palaeura hispanica Smith, descubierto por primera vez en el sinclinal de Algodor- Milagro en los Montes de Toledo, y que ahora se identifica en el sinclinal del Guadarranque en las Villuercas. Se trata de un ejemplar completo conservado por su cara dorsal, que muestra la región central del disco erosionada dejando ver las placas orales. Uno de los brazos se halla torsionado, con su extremo ventral vuelto hacia arriba. La conformación de los brazos de P. neglecta Schuchert (Darriwiliense medio de Bohemia y el oeste de Inglaterra) presenta suficientes diferencias con P. hispanica (Darriwiliense medio de la Zona Centroibérica), como para considerar a ambos taxones como especies distintas, en lugar de subespecies geográficas. El ejemplar estudiado se expone en el Centro de Interpretación del Fósil de Navatrasierra, dependiente del Geoparque extremeño Villuercas-Ibores- Jara Fossil asterozoans are extremely rare in the Middle and Upper Ordovician of southwestern Europe, especially because they disarticulate rapidly after death and have a lower potential of fossilization. This paper presents the second record of Palaeura hispanica Smith in the Central Iberian Zone. This ophiuroid was first discovered in the Algodor-Milagro syncline in the Toledo Mountains, and is now characterized in the Guadarranque syncline in Las Villuercas. The single described specimen is preserved by its dorsal face, with the eroded central region of the disc showing the oral plates. One of the arms is turned up, showing details of its ventral surface. Plates from the arms of P. neglecta Schuchert (Middle Darriwilian of Bohemia and western England) show differences with P. hispanica (Middle Darriwilian of the Central Iberian Zone), suggesting they are different species instead of geographical subspecies. The specimen studied is currently exhibited at the Interpretation Center of the Fossil of Navatrasierra, belonging to the Villuercas-Ibores-Jara UNESCO Global Geopark (Extremadura, west of Spain)

Comunicaciones presentadas en la LXVII Sesión Científica / Peñarroya-Pueblonuevo (Córdoba) 22 de noviembre de 2019, Se presentan nuevos trilobites, braquiópodos y moluscos del Ordovícico Medio encontrados en el Dominio de Obejo-Valsequillo (suroeste del Macizo Ibérico), donde las localidades paleontológicas de dicha época son muy raras. Los nuevos datos de fósiles ordovícicos de Campillo de Llerena (Badajoz), identificados en cantos y bloques lutíticos incorporados a una formación carbonífera sinorogénica, permiten asegurar la presencia de horizontes del Oretaniense inferior derivados de un área fuente probablemente cercana. En el yacimiento paleontológico de Peñaladrones (noreste de Belmez, Córdoba), sumamos un bivalvo y dos gasterópodos a las listas precedentes. Entre ellos destaca el bellerofóntido Tritonophon sp., un género restringido en el ámbito del Ordovícico Medio ibero-armoricano a dos localidades del Dominio de Obejo-Valsequillo. Finalmente, en la localidad de Mina Guillermín (sur de Alcaracejos, Córdoba) sumamos también nuevos registros de trilobites y moluscos del Oretaniense superior-Dobrotiviense inferior., Instituto de Geociencias, Consejo Superior de Investigaciones Científicas, España, Instituto de Geociencias, Universidad Complutense de Madrid, España

Los restos de asterozoos son sumamente escasos en el Ordovícico Medio y Superior del suroeste de Europa, si bien la auténtica diversidad de estos equinodermos está largamente enmascarada por su dificultad de fosilización. En este trabajo se presenta la segunda localidad centroibérica donde se registra el ofiuroideo Palaeura hispanica Smith, descubierto por primera vez en el sinclinal de Algodor- Milagro en los Montes de Toledo, y que ahora se identifica en el sinclinal del Guadarranque en las Villuercas. Se trata de un ejemplar completo conservado por su cara dorsal, que muestra la región central del disco erosionada dejando ver las placas orales. Uno de los brazos se halla torsionado, con su extremo ventral vuelto hacia arriba. La conformación de los brazos de P. neglecta Schuchert (Darriwiliense medio de Bohemia y el oeste de Inglaterra) presenta suficientes diferencias con P. hispanica (Darriwiliense medio de la Zona Centroibérica), como para considerar a ambos taxones como especies distintas, en lugar de subespecies geográficas. El ejemplar estudiado se expone en el Centro de Interpretación del Fósil de Navatrasierra, dependiente del Geoparque extremeño Villuercas-Ibores- Jara, Fossil asterozoans are extremely rare in the Middle and Upper Ordovician of southwestern Europe, especially because they disarticulate rapidly after death and have a lower potential of fossilization. This paper presents the second record of Palaeura hispanica Smith in the Central Iberian Zone. This ophiuroid was first discovered in the Algodor-Milagro syncline in the Toledo Mountains, and is now characterized in the Guadarranque syncline in Las Villuercas. The single described specimen is preserved by its dorsal face, with the eroded central region of the disc showing the oral plates. One of the arms is turned up, showing details of its ventral surface. Plates from the arms of P. neglecta Schuchert (Middle Darriwilian of Bohemia and western England) show differences with P. hispanica (Middle Darriwilian of the Central Iberian Zone), suggesting they are different species instead of geographical subspecies. The specimen studied is currently exhibited at the Interpretation Center of the Fossil of Navatrasierra, belonging to the Villuercas-Ibores-Jara UNESCO Global Geopark (Extremadura, west of Spain)

[EN] The revision of the Upper Ordovician sequence west of Noguera de Albarracín (Teruel Province) yielded two horizons with trilobites and other fossils. The oldest horizon occurs toward the middle part of the Bronchales Formation and is of Berounian (late Sandbian-early Katian) age, bearing trinucleids (Deanaspis), illaenids (Vysocania) and dalmanitids (Dalmanitina). The youngest studied horizon is located at the base of the Cystoid Limestone Fm. and yielded pliomerids (Ovalocephalus) and illaenids (Cekovia?) of Kralodvorian (Katian 3-4) age. The record of Upper Ordovician fossils in the Castilian branch of the Iberian Range is particularly scarce, and the Bronchales Fm. association now described supports the correlation of this unit with the Fombuena Fm. of the Aragonian branch. Towards the N and NW of the Tremedal inlier, Berounian rocks are absent due to non-deposition or erosion before younger calcareous sedimentation took place. This revision allows to locate a trinucleid trilobite-bearing horizon briefly mentioned in the mid-20th Century but never described or figured. Herein we pinpoint the stratigraphical position of this classical horizon and, due to its importance, present a short systematic section on Deanaspis cf. seunesi., [ES] Se revisa la sucesión del Ordovícico Superior al oeste de Noguera de Albarracín (Teruel), identificándose dos horizontes con trilobites y otros fósiles. El más antiguo se sitúa hacia la parte media de la Formación Bronchales y es de edad Berouniense (Sandbiense/Katiense en la escala global), conteniendo trinucleidos (Deanaspis), illaénidos (Vysocania) y dalmanítidos (Dalmanitina). El horizonte siguiente se localiza en la base de la Fm. Caliza de Cistoideos y es de edad Kralodvoriense (Katiense 3-4), con plioméridos (Ovalocephalus) e illaénidos (Cekovia?). El registro de trilobites y braquiópodos del Ordovícico Superior es particularmente escaso en la rama castellana, donde las formas representadas en la Fm. Bronchales permiten la correlación de esta unidad con la Fm. Fombuena de la rama aragonesa. Al N y NO del Macizo del Tremedal, los materiales berounienses no se depositaron (o fueron erosionados) previamente a las unidades calcáreas del Kralodvoriense. La localización del nivel con Deanaspis cf. seunesi permite situar estratigráficamente las citas locales de trinucleidos, mencionados desde mediados del siglo XX pero nunca descritos o figurados, razón por la cual se añade un pequeño apartado sistemático para este taxón., Este trabajo es una contribución a los proyectos CGL2017- 87631-P del MINEICO e IGCP 653 de la IUGS-UNESCO.

Se revisa la sucesión del Ordovícico Superior al oeste de Noguera de Albarracín (Teruel), identificándose dos horizontes con trilobites y otros fósiles. El más antiguo se sitúa hacia la parte media de la Formación Bronchales y es de edad Berouniense (Sandbiense/Katiense en la escala global), conteniendo trinucleidos (Deanaspis), illaénidos (Vysocania) y dalmanítidos (Dalmanitina). El horizonte siguiente se localiza en la base de la Fm. Caliza de Cistoideos y es de edad Kralodvoriense (Katiense 3-4), con plioméridos (Ovalocephalus) e illaénidos (Cekovia?). El registro de trilobites y braquiópodos del Ordovícico Superior es particularmente escaso en la rama castellana, donde las formas representadas en la Fm. Bronchales permiten la correlación de esta unidad con la Fm. Fombuena de la rama aragonesa. Al N y NO del Macizo del Tremedal, los materiales berounienses no se depositaron (o fueron erosionados) previamente a las unidades calcáreas del Kralodvoriense. La localización del nivel con Deanaspis cf. seunesi permite situar estratigráficamente las citas locales de trinucleidos, mencionados desde mediados del siglo XX pero nunca descritos o figurados, razón por la cual se añade un pequeño apartado sistemático para este taxón, The revision of the Upper Ordovician sequence west of Noguera de Albarracín (Teruel Province) yielded two horizons with trilobites and other fossils. The oldest horizon occurs toward the middle part of the Bronchales Formation and is of Berounian (late Sandbian-early Katian) age, bearing trinucleids (Deanaspis), illaenids (Vysocania) and dalmanitids (Dalmanitina). The youngest studied horizon is located at the base of the Cystoid Limestone Fm. and yielded pliomerids (Ovalocephalus) and illaenids (Cekovia?) of Kralodvorian (Katian 3-4) age. The record of Upper Ordovician fossils in the Castilian branch of the Iberian Range is particularly scarce, and the Bronchales Fm. association now described supports the correlation of this unit with the Fombuena Fm. of the Aragonian branch. Towards the N and NW of the Tremedal inlier, Berounian rocks are absent due to non-deposition or erosion before younger calcareous sedimentation took place. This revision allows to locate a trinucleid trilobite-bearing horizon briefly mentioned in the mid-20th Century but never described or figured. Herein we pinpoint the stratigraphical position of this classical horizon and, due to its importance, present a short systematic section on Deanaspis cf. seunesi

[EN] Large bedding exposures, intensively bioturbated by the producer of Daedalus desglandi (Rouault), are reported from the lower part of the Ordovician succession (lower Arenigian “Intermediate Beds”) east of the town of Fontanarejo (Ciudad Real Province). This ichnofossil corresponds to a vertical spreiten burrow, spirally twisted inwards, initiated from a single point in the water-sediment surface on a very shallow marine environment. Most of the recorded specimens are transverse sections of D. desglandi in epirelief preservation, reaching a density of 250-275 specimens per square meter, and extending over an area up to 12000 m2. The magnitude of this extremely crowded monoichnospecific assemblage makes this locality unique in the world’s ichnological record for the Paleozoic and reinforces its future inventory in the list of the Spanish Geosites of international interest. Similar occurrences of D. desglandi in the Naturtejo Geopark of Portugal reached a maximum of 70 m2 (Serra de Muradal) and 700 m2 (Fonte Longa geosite) for epichnial records of a single bed, [ES] Se presenta el hallazgo de un gran afloramiento cuarcítico situado al este de Fontanarejo (Ciudad Real), afectado por una intensa bioturbación a cargo del productor de Daedalus desglandi (Rouault). La localidad se sitúa en los niveles inferiores de las “Capas Intermedias” (Arenigiense inferior) y el icnofósil corresponde a una excavación vertical con conexiones convexas, con desarrollo helicoidal hacia el interior, que se inicia desde un punto situado inicialmente en la interfase agua-sedimento, en un ambiente marino muy somero. La mayoría de los ejemplares observados son secciones transversales de D. desglandi conservados como epirelieves, que alcanzan la increíble densidad de 250-275 ejemplares/m2, en un área que podría alcanzar los 12000 m2. La magnitud de esta asociación icnoespecífica, tan masiva, convierte a la localidad en un referente único a nivel mundial del registro icnológico paleozoico, y promueve nuestra propuesta para que sea inventariada en la lista de los Lugares Geológicos Españoles de interés internacional., Este trabajo es una contribución a los proyectos IBEROR (CGL2012-39471) del MINECO e IGCP 653 (IUGS-UNESCO).

Se presenta la "Ruta de las huellas fósiles", realizada en el casco urbano de Monsagro (Sierra de Franda, Salamanca). Mediante seis paneles didácticos e interpretativos, que induyen el acceso "online " desde las nuevas tecnologías (smartphonq tatíets, ipod....)ainfonnadóncomplementariaimplementadaen videos códigos QR, geoapps y juegos se han promodonado y divulgado los contenidos geológicos de la zona, basados prinapalmente en el interés paleontológico de sus icnofósiles, atribuidos a diversos tipos de gusanos y trilobites durante el Ordovídco Inferior, y en el interés geomorfblógico de sus cresterías cuarcrticas con relieve apalachiense, del encajamiento fluvial del río Agadón y de sus fomradones superficiales como canchales Los visitantes señalan como fortalezas de la ruta su fácil y didáctico recorrido, así como la implicación ciudadana en la conservadón de las icnitas, We present the “Ruta de las huellas fosiles", implemented in the village of Monsagro (Francia mountain range, Salamanca). Through six didactic and interpretative panels, we have included online access to the new technologies (smartphones, tablets, digital audio players...) and complementary information implemented in videos, QR codes, geoapps and games. The geological contents of the area are based mainly on the paleontological interest of its ichnofossils essentiatly produced by worms and trilobites of Lower Ordovician age, and the geomorphological interest of its appalachian relief, theAgadon river fluvial incision and its surficial formations. The visitors point out as strength of the route its easy and didactic character, as well as the direct citizen involvement in the conservation of the ichnofossils

Se presenta la "Ruta de las huellas fósiles", realizada en el casco urbano de Monsagro (Sierra de Franda, Salamanca). Mediante seis paneles didácticos e interpretativos, que induyen el acceso "online " desde las nuevas tecnologías (smartphonq tatíets, ipod....)ainfonnadóncomplementariaimplementadaen videos códigos QR, geoapps y juegos se han promodonado y divulgado los contenidos geológicos de la zona, basados prinapalmente en el interés paleontológico de sus icnofósiles, atribuidos a diversos tipos de gusanos y trilobites durante el Ordovídco Inferior, y en el interés geomorfblógico de sus cresterías cuarcrticas con relieve apalachiense, del encajamiento fluvial del río Agadón y de sus fomradones superficiales como canchales Los visitantes señalan como fortalezas de la ruta su fácil y didáctico recorrido, así como la implicación ciudadana en la conservadón de las icnitas We present the “Ruta de las huellas fosiles", implemented in the village of Monsagro (Francia mountain range, Salamanca). Through six didactic and interpretative panels, we have included online access to the new technologies (smartphones, tablets, digital audio players...) and complementary information implemented in videos, QR codes, geoapps and games. The geological contents of the area are based mainly on the paleontological interest of its ichnofossils essentiatly produced by worms and trilobites of Lower Ordovician age, and the geomorphological interest of its appalachian relief, theAgadon river fluvial incision and its surficial formations. The visitors point out as strength of the route its easy and didactic character, as well as the direct citizen involvement in the conservation of the ichnofossils

Trabajo presentado en el IX Congreso Geológico de España, celebrado en Huelva (España), del 12 al 14 de septiembre de 2016, [ES] Se actualiza el registro paleontológico del Ordovícico (trilobites, graptolitos, braquiópodos, equinodermos, moluscos, conodontos) en el Dominio de Obejo-Valsequillo) representado en cinco localidades fosilíferas. Dos de ellas (sur de Alcaracejos y noreste de Belmez) corresponden a la llamada “Unidad Parautóctona” y las tres restantes (Campillo de Llerena, Villaharta y oeste de Adamuz) a las “Unidades Alóctonas”. Las asociaciones paleontológicas guardan ciertas semejanzas con las de la Zona Centroibérica pero representan retazos de una plataforma marina de gradiente opuesto a la surcentroibérica (profundización hacia el sur y suroeste vs. profundización hacia el norte y noreste). Ello implica grandes desplazamientos, congruentes con el modelo alóctono de la nueva Zona Galicia-Ossa Morena, tal vez en continuidad paleogeográfica hacia el noroeste con el Autóctono del suroeste de Iberia., [EN] The palaeontological record from the Ordovician of the Obejo-Valsequillo Domain is here updated and it includes trilobites, graptolites, brachiopods, echinoderms, mollusks and conodonts, coming from five fossil localities. Two of them (south of Alcaracejos and northeast of Belmez) correspond to the so-called “Parautochthonous Unit” and the remaining three (Campillo de Llerena, Villaharta and west of Adamuz) to the “Allochthonous Units”. These assemblages show some relationships with those from the Central Iberian Zone, but possibly represent the remains of a marine shelf under a gradient opposite to that of the south Central-Iberian one: i.e., deepening to the south and southwest instead of towards the north and northeast, respectively. This implies Variscan megadisplacements, congruent with the general allochthonous model of the new Galicia–Ossa-Morena Zone, and perhaps palaeogeographic continuity to the northwest with the Southwestern Iberian Autochthon during the Lower Palaeozoic., Este trabajo es una contribución al proyecto CGL2012-39471 del MINECO.

The discovery of Didymograptus (Didymograptus) artus Elles and Wood in the Ordovician section of the Vidrias Cape (Atlantic coast of Spain), constitutes the first record of early Oretanian (= mid Darriwilian) rocks in the Cantabrian Zone of the Iberian Massif. The fossil locality lies in a shaly intercalation towards the middle part of an easternmost equivalent of the «Sabugo Quartzite» of the Navia Domain (West Asturian-Leonese Zone), so far unknown in the reference section for the Ordovician of the Cantabrian Zone of the nearby Peñas Cape. Correlations of the studied strata by previous authors are also reviewed, and the existence of a fault is suggested to occur between the «Peñas» and «Vidrias» members of the Luarca Formation on the famous section of the Peñas Cape

4 páginas, 2 figuras.-- Trabajo presentado en la 44ª Sesión Científica, Jaén, 2008., Lower and Middle Ordovician rocks outcropping in the Cabañeros National Park (Central Iberian Zone) are being explored within a mapping project aimed at identifying geosites representative of the geological and paleontological heritage on this natural area. Ongoing field-work has led to the discovery of three fossil localities that bring out significant paleontological data relevant to the whole Iberian Massif. The oldest comes from the upper part of the Armorican Quartzite Fm. (Floian/middle Arenigian) and is a large ichnofossil identified as Tumblagoodichnus? isp., which probably represents a shallow burrow filled by collapse of sand from above, and dug as a temporary refuge by a large arthropod. The trace is 45 cm wide, much bigger than the large arthropod traces previously reported from the Iberian Ordovician (rare Cruziana reach up to 26 cm in width). The second fossil locality lies towards the middle part of the overlying Marjaliza Beds (Dapingian to lower Darriwilian/middle-upper Arenigian) and is represented by a thick coquina of paleotaxodont and paleoheterodont bivalves, apparently formed due to a catastrophic event (an exceptional storm?) that transported and entombed en masse millions of individuals now preserved as complete specimens with closed valves. This local abundance strongly contrasts with the scarcity of Arenigian bivalves preserved in the Cruziana sandstone facies of SW Europe. Finally, the youngest locality is a rich fossiliferous bed of lower Oretanian (Darriwilian) age recorded in the Navas de Estena Shales, where the brachiopod genus Eodalmanella (Ranorthidae) makes its second European occurrence and reinforces the Ibero-Bohemian paleobiogeographic affinities., Acción Estratégica 56/2006 de la Red de Parques Nacionales. Proyecto PATRIORSI, CGL2006-07628/BTE. Proyecto PICG 503 del Programa Internacional de Geociencias (IUGS-UNESCO) y las actividades del Grupo de Investigación Precámbrico y Paleozoico Perigondwánico de la Universidad Complutense de Madrid.

Lower and Middle Ordovician rocks outcropping in the Cabañeros National Park (Central Iberian Zone) are being explored within a mapping project aimed at identifying geosites representative of the geological and paleontological heritage on this natural area. Ongoing field-work has led to the discovery of three fossil localities that bring out significant paleontological data relevant to the whole Iberian Massif. The oldest comes from the upper part of the Armorican Quartzite Fm. (Floian/middle Arenigian) and is a large ichnofossil identified as Tumblagoodichnus? isp., which probably represents a shallow burrow filled by collapse of sand from above, and dug as a temporary refuge by a large arthropod. The trace is 45 cm wide, much bigger than the large arthropod traces previously reported from the Iberian Ordovician (rare Cruziana reach up to 26 cm in width). The second fossil locality lies towards the middle part of the overlying Marjaliza Beds (Dapingian to lower Darriwilian/middle-upper Arenigian) and is represented by a thick coquina of paleotaxodont and paleoheterodont bivalves, apparently formed due to a catastrophic event (an exceptional storm?) that transported and entombed en masse millions of individuals now preserved as complete specimens with closed valves. This local abundance strongly contrasts with the scarcity of Arenigian bivalves preserved in the Cruziana sandstone facies of SW Europe. Finally, the youngest locality is a rich fossiliferous bed of lower Oretanian (Darriwilian) age recorded in the Navas de Estena Shales, where the brachiopod genus Eodalmanella (Ranorthidae) makes its second European occurrence and reinforces the Ibero-Bohemian paleobiogeographic affinities

The studied region is situated in the Aveiro district, about 50 km SW of Oporto (northern Portugal) and has a rich geological, biological and cultural heritage. The Arouca Geopark was formally established there in late 2007, under the auspices of Arouca’s Municipal Chamber, to reunite 36 geosites from which some of them involve remarkable Ordovician and Silurian rocks and fossils. Outcrops of both periods belong to the Valongo- Tamames syncline of the Central Iberian Zone. Lower Palaeozoic rocks around the Canelas Slate Quarry are of special interest, leading to the creation of a geotouristic route visiting three Ordovician units (Santa Justa quartzites, Valongo shales and Sobrido quartzite plus glaciomarine diamictites) and one Silurian (graptolitic black shales), as well as a Roman gold mine dug in the Lower Ordovician quartzites. However, the most outstanding geosite is the quarry itself, where Middle Ordovician giant trilobites (up to 70 cm in size) and trilobite clusters (up to thousands of specimens) occur in large slabs of slate and are recovered during the exploitation. The Geological Interpretation Centre of Canelas, located near the quarry and open since 2006, is one of the main tourist attractions of the Arouca Geopark, created to preserve and disseminate knowledge about trilobites and the Ordovician world, and having received more than 10,000 visitors in its first 17 months

42 páginas, 17 figuras, 5 fotos., [EN] The Ordovician System outcrops extensively in the northeastern of Portugal, in the septentrional sector of the Central-Iberian Zone. The level of lithostratigraphic knowledge about these materials is notably lower than that of identical materials in other Portuguese regions and in a comparable peleogeographic scope. In this sense, the Ordovician of Trás-os-Montes remains, in many aspects, terra incognita. Recent fieldwork focused in the Ordovician biostratigraphy of northeastern Portugal lead us to consider the conveniente of making a deeper lithostratigraphical revision of these materials. It is a much needed amendment due to the proliferation of informal units and operative divisions that exist in the region, whose significance also varies for each of the authors, and the whole totality was examined under the requirements established by the international Stratigraphic Guide. The new lithostratigraphic scheme here proposed, unified for the entire region, considers the formal definition of 19 lithostratigraphical units, most of them of siliciclastic nature. The stratigraphic succession includes one group, eight formations, seven members and three individual beds. Each unit of equal or lower range than the Formation is clearly defined regarding its lithology and boundaries at the stratotype, considering its regional aspects, subdivisions, dating, sedimentary environment and detailed revision of the synonymy, as well the thickness ascribed from the previous authors to each concrete assemblage. The stratigraphic study allowed us to characterize and contextualize several units attributed to the Upper Ordovician, scarcely or partially unknown in the region until now, as well as the detection of stratigraphic gaps with different ranges and generally with great paleogeograhic interest. The new lithostratigraphic scheme here formalized for the Ordovician of Trás-os-Montes allows a precise knowledge and correlation of this region with the remaining Portuguese Central-Iberian Zone (Valongo, Buçaco, Amêndoa-Maçâo) and in the frame of southwestern Europe., [PT] A recente realizaçâo de trabalhos, centrados no estabelecimento da bioestratigrafia do Ordovícico do nordeste de Portugal (Zona Centro-Ibérica), conduziu a urna profunda revisiâo litoestratigáfica destes materiais, â luz dos requerimentos litoestratigráficos estabelecidos pelo Guia Estratigráfico Internacional e justificada pela grande proliferaçâo de unidades informais e divisôes operativas existentes na regiâo. Esta nova proposta, unificada para a regiâo transmontana, contempla a definiçâo formal de um total de 19 unidades litoestratigráficas, a maioria das quais de natureza siliciclástica, repartidas por um grupo, oito formaçôes, sete membros e três camadas. Este estudo permitiu caracterizar e contextualizar diversas unidades atribuídas ao Ordovícico Superior, até agora praticamente ignoradas na regiâo, assim como a detecçâo de lacunas estratigráficas de grande interesse paleogeográfico. O novo esquema litoestratigráfico, agora apresentado, permite correlacionar de forma precisa e nivelar o conhecimento relativamente à restante Zona Centro-Ibérica portuguesa (Valongo, Buçaco, Amêndoa-Maçâo) e ao restante Ordovícico do sudoeste da Europa.

The holotype of''Echinosphaerites'' murchisoni Verneuil and Barrande 1855 is reviewed, and proposed as the type species of Oretanocalix gen. nov. The new genus is characterised by an elongate theca of medium size, that aborally shows a pair of long and prominent parietal septa interpreted as mesenterical; mouth narrow and elongate, with five very short ambulacra, the anterior comparatively reduced, ending in a set of few brachiole facets. The presence of a 2-1-2 ambulacraI system with an atrophied A-ambulacrum could denote a simplification leading to the 2-2 pattern of Calix or Phlyctocystis. The new genus ranges from Oretanian to Dobrotivian in age, and is distributed in Central Spain, the Moroccan Anti-Atlas and the French Armorican Massif

24 páginas, 4 figuras, 2 láminas, 1 tabla., [EN] New palaeontological data from Upper Ordovician formations of NW Spain (Caurel-Peñalba and Truchas synclines) are documented. The «Trigal limestones» of the Casaio Formation, the La Aquiana Formation and calcareous pebbles of the Rozadais Formation have yielded conodont assemblages indicating the Ashgillian Anzorphognathus ordovicicus Biozone. Scabbardella altipes (Henningsmoen), Panderodus gracilis (Branson & Mehl), Anzorplzognathus ordovicicus Branson & Mehl, Amorphogizatlzus sp., Sagittodontiíza robusta Knüpfer, Sagittodontina? sp., Icriodella sp. and Hamarodus europaeus (Serpagli) have been identified and described. Stratigraphic correlations between the different structural units are discussed, as well as the regional context of the Upper Ordovician sedimentation. According to a new model which conciliates the local geotectonic setting with the global paleoclimatic events, the Rozadais Formation underwent a glaciomarine influence during the Hirnantian, and is clearly younger in age that other Ashgill units which consist or include pre-Hirnantian limestones (La Aquiana and Casaio formations)., [ES] Se presentan las asociaciones de conodontos ordovícicos registradas en las «calizas del Trigal» de la Formación Casaio, en la Formación La Aquiana y en los cantos calcáreos englobados en la Formación Rozadais, pertenecientes a afloramientos del sinclinorio de Truchas (norte de la Zona Centroibérica) y del sinclinal del Caurel-Peñalba (sur de la Zona Asturoccidental-leonesa). Las formas identificadas son Scabbardella altipes (Henningsmoen), Paizdei~odus gracilis (Branson y Mehl), Amorphognathus ordovicicus Branson y Mehl, Anzorphognathus sp., Sagittodoiztiiza robusta Knüpfer, Sagittodontina? sp., Icriodella sp. y Hanzarodus europaeus (Serpagli), que corresponden a la Biozona de Aínorphognathus ordovicicus del Ashgill y se describen e ilustran en el apartado sistemático. En función de estos datos y sus circunstancias estratigráficas, se propone una correlación general de las unidades del Ordovícico Superior de la región, presentándose un nuevo modelo que armoniza el marco geotectónico local con los eventos globales del Ashgill comunes a la región nord-gondwaniense. En este sentido, se considera un influjo glaciomarino para la Formación Rozadais (Hirnantiense), cuyo depósito no sería coetáneo con las unidades calcáreas pre-Hirnantienses (Trigal y La Aquiana)., Este trabajo se inscribe en los proyectos PB94-1330 y PB96-0839 de la DGES, y sus resultados son también una contribución al Proyecto 410 del PICG (IUGS-UNESCO), así como al Proyecto «Iberia» del Programa EUROPROBE (European Science Foundation). La participación del primer autor fue posible gracias a una beca postdoctoral de la Comunidad de Madrid, que lleva por título «Aplicación de Conodontos en bioestratigrafía de alta resolución y geotermometría de materiales ordovícicos y silúricos de España» (1998-1999).

The holotype of''Echinosphaerites'' murchisoni Verneuil and Barrande 1855 is reviewed, and proposed as the type species of Oretanocalix gen. nov. The new genus is characterised by an elongate theca of medium size, that aborally shows a pair of long and prominent parietal septa interpreted as mesenterical; mouth narrow and elongate, with five very short ambulacra, the anterior comparatively reduced, ending in a set of few brachiole facets. The presence of a 2-1-2 ambulacraI system with an atrophied A-ambulacrum could denote a simplification leading to the 2-2 pattern of Calix or Phlyctocystis. The new genus ranges from Oretanian to Dobrotivian in age, and is distributed in Central Spain, the Moroccan Anti-Atlas and the French Armorican Massif

A typical example of the Helminthopsis ichnogulld formed by deep deposit-feeder tiers is presented from an Upper Ordovician shallow marine succession in Central Spain. The monospecific ichnoassociation is composed by Helminthopsis abeli Ksiazkiewicz, massively recorded from a single bed within a sillciclastic alternation with some storm influence ofCaradoc age, in the lower part of the "Bancos Mixtos" Formation, south of the town of Torrenueva (Province of Ciudad Real)

A typical example of the Helminthopsis ichnogulld formed by deep deposit-feeder tiers is presented from an Upper Ordovician shallow marine succession in Central Spain. The monospecific ichnoassociation is composed by Helminthopsis abeli Ksiazkiewicz, massively recorded from a single bed within a sillciclastic alternation with some storm influence ofCaradoc age, in the lower part of the "Bancos Mixtos" Formation, south of the town of Torrenueva (Province of Ciudad Real)

Some scarce and bad preserved bivalves have been described from few localities lying at the upper part of the Armorican quartzite facies in Central Spain. Middle Arenig faunas include two palaeotaxodont forms (Praenucula oehlerti and Cardiolaria sp.), and two different palaeoheterodonts (Modiolopsis sp. and ?Actinodontoida indet.). Previous reports of other Arenig bivalves, especially actinodontoids, from coeval quartzites of northwestern, Central and northeastern Spain, as well as from Central Portugal, have been also briefly examined. The Iberian faunas show close affinities with the well known Arenig assemblages from the «Grès armoricain» of Western France, and add new data for the scenic reconstruction of the Lower Ordovician bivalve radiations on the northwestern Gondwanan shelves

The first record outside Bohemia of the recumbent diploporid Aristocystites metroi is presented. It consists of a remarkable specimen from the Dobrotivian shales of CaIzada c/e Calatrava (Central Iberian Zone). The Spanish occurrence of the species is markedly older (Dobrotivian: Middle Ordovician) than in Bohemia (Zahoranlan and Kosovian; Upper Ordovician). Our specimen derives also from much shallower environments with respect to the type material

The first record outside Bohemia of the recumbent diploporid Aristocystites metroi is presented. It consists of a remarkable specimen from the Dobrotivian shales of CaIzada c/e Calatrava (Central Iberian Zone). The Spanish occurrence of the species is markedly older (Dobrotivian: Middle Ordovician) than in Bohemia (Zahoranlan and Kosovian; Upper Ordovician). Our specimen derives also from much shallower environments with respect to the type material

Upper Ordovician rocks have been characterized for the first time in the Cantabrian Zone of the Hesperian Massif. The sequence consists of a lower siliciclastic unit of Caradoc-(‘basal Ashgill age developed as an alternation of shales, siltstones and sandstones, overlain by an upper unit of fossiliferous limestones with marly intercalations, of pre-Hirnantian (mainly Cautleyan-Rawtheyan) age. Ashgill fossils are fairly abundant in the limestone unit, and there have been identified brachiopods of the «Nicolella fauna», echinoderms of the «Heliocrinites fauna» and trilobites of the Qvalocephalus biofacies

2 páginas.-- Comunicación presentada en el IV Congreso Nacional de Geología, Alcalá de Henares, 1996., This work deals with the stratigraphical and palaeontological study of the vulcanosedimentary Castro Formation in its type locality, close to Cabo Peñas (Asturias, Cantabrian Zone). The formation consists of three members: a lower member of alternating volcanoclastic and sedimentary rocks, a middle member, mostly basaltic, and an essentially upper calcareous member (Viodo Mb.). On the basis of the palaeontological data and the preliminary results from the correlation with Cabo Vidrias section (west of Cabo Peñas), a Middle Ordovician age is established for the lower member. The Viodo Mb. is Lower Silurian in age as shown by an abundant fossiliferous content. So far, fossils supporting the occurrence of the Upper Ordovician have not been found, although it could be represented in the middle member of the formation., Este trabajo es una contribución al proyecto "Bioestratigrafía del Ordovícico de la Zona Cantábrica y margen de la Asturoccidental-leonesa" (DGICYT, PB 91-0671).

Fossiliferous shales of the Luarca Formation are identified for the first time in the southern part of the Pliegues y Mantos domain of the western Cantabrian Zone. The outcrop consists of 10,6 m of dark shales and micaceous silts tones, tectonically intercalated between the La Matosa (Middle and Upper Cambrian) and Tanes (Arenig) members of the Barrios Formation, close to the classical section of this unit. The occurrence of a diverse assemblage of trilobites, graptolites, ostracods, brachiopods, echinoderms, molluscs and some acritarchs and chitinozoans confirms a Middle Ordovician age for the shales, whereas the age of the top of the Barrios Formation does not exceed the Arenig

[ES] Se analiza la distribución vertical de más de doscientas especies fósiles reconocidas en las «capas con Tristani» de España central, cuya estratigrafía también es objeto de una primera revisión. La fauna está compuesta principalmente por trilobites, moluscos, braquiópodos, equinodermos, crustáceos y graptolitos, entre los cuales algunos géneros y especies se citan por vez primera en España. La extensión vertical restringida de ciertos trilobites, braquiópodos y graptolitos permite la caracterización de algunas Biozonas que tienen grandes posibilidades de ser correlacionadas con otras áreas peninsulares y el Macizo Armoricano francés. En el trabajo empleamos la Serie Dobrotiviense de Bohemia como sustituto (aprox.) del Llandeilo de la escala patrón británica, ya que este último es muy difícil de caracterizar en el sector estudiado por corresponder a un contexto biogeográfico y paleogeográfico muy diferente del de las áreas-tipo del Ordovícico., [EN] The vertical distribution of more than two-hundred fossil species determined in the "Tristani beds" of Central Spain is analized. At the same time, their stratigraphy is reviewed. Its fauna is composed mainly by trilobites, molluscs, brachiopods, echinoderms, crustaceans and graptolites, some of whose species are listed for the first time in Spain. Ihe restricted vertical distribution of certain trilobites, brachiopods and graptolites allows the charachterization of several biozones with a high possibility of correlation with other peninsular areas and with the French Armorican Massif. In this study we make use of the Dobrotivian Series of Bohemia as a substitute of the Llandeilo of the British standard scale, as the latter proves to be exceedingly difficult to charachíerize in the studied region, because of its belonging to a biogeographic and palaeogeographic background very different from that of the Ordovician type-areas.

3 páginas, 1 figura.-- Trabajo presentado en la 4ª Sesión Científica, Granada 1987., The Ordovician outcrop at NW Adamuz (Córdoba province), previously regarded as belonging to in the Ossa Morena Zone by some authors, contains several fossiliferous levels of Lower Llanvirn, Upper Llanvirn-Llandeilo and Caradoc (pre-Actonian) age. The Central lberian affinities of the faunas constitute an additional argument for the consideration of the Obejo-Valsequillo-Puebla de la Reina Domain as the southern margin of the Central Iberian Zone during the Paleozoic., Este artículo es una contribución al Proyecto "Bioestratigrafia y Paleocología del Paleozoico inferior del SO, del Macizo Hespérico", financiado por el CSIC-CAICYT.

The distribution of the faunas and sediments of mediterranean character is related to paleogeographical aspects (epicratonic seas at high latitudes surrounding the Gondwanan continent) as well as to global transgressive-regressive cycles which, together with some oceanic currents, facilitated the interprovincial dispersal of certain characteristic elements throughout several epochs of the Ordovician Period, La distribución de las asociaciones fosilíferas de «tipo mediterráneo» está relacionada con factores paleogeográficos (mares epicratónicos de latitudes elevadas próximos al continente de Gondwana) y con los ciclos globales de transgresión-regresión que, combinados con las corrientes marinas, facilitaron la dispersión interprovincial de algunos elementos característicos a 10 largo de diversas etapas del Período Ordovícico