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Se presenta una nueva sección bioestratigrafica de la parte basal de la Formación Sueve. La nueva sección se suma a las nuevesecciones descritas en estudios previos, relativos al sector septentrional del manto de Laviana. Los horizontes fosilíferos muestreados seintegran en la Biozona del graptolito Didymograptus murchisoni, indicativo de una edad Oretaniense tardío o Darriwiliense tardío no terminal según las respectivas escalas regional y global. Entre los resultados paleontológicos destaca el hallazgo de algunos fósiles raros o desconocidos en la Fm. Sueve. El graptolito Pseudoclimacograptus cf. scharenbergi (Lapworth) se cita por vez primera en el SO de Europa a través de un ejemplar conservado tridimensionalmente; el rostroconcha Ribeiria apusoides Schubert y Waagen se identifica por segunda vez en el Ordovícico de España (tras un primer registro centroibérico en Almadén); y el trilobites Crozonaspis morenensis Hammann confirma su presencia en el Oretaniense superior de la Fm. Sueve con un material más abundante y mejor conservado. Finalmente, el descubrimiento de un trilobites rafiofórido en el afloramiento estudiado abre la posibilidad de encontrar nuevos ejemplares de estos rarísimos trilobites a escala del Ordovícico ibérico.

Comunicaciones presentadas en la LXXI Sesión Científica / Geoparque Montañas do Courel (Lugo), 26 de noviembre de 2021, [EN] A third specimen of Megistaspis (Ekeraspis) cf. hammondi is described from the most important Ordovician Burgess Shale-type Fossil-Lagerstätte in Morocco. The trilobite specimens with soft-part preservation are located in late Tremadocian levels within the Fezouata Formation, but are very rare. The studied specimen preserves the right antenna, and nine appendages under the right side of the exoskeleton, only evident when a break in the rock released part of the exoskeleton and revealed the underlying biramous appendages. These mostly consist of endopods, but also at least a couple of exopods, recognizable by their long lamellae. The first endopod seems to correspond to the distal tip of the third cephalic appendage, while the rest are thoracic appendages. The features of the preserved antenna indicate that most such appendages in other specimens from the same area are created or enhanced during preparation. Besides the studied asaphid, soft-part preservation of digestive tract and appendages are known from four coeval species, totalling about fifty published specimens. But it is quite possible that, like in the present specimen, biramous appendages may be preserved under the carapace of other specimens with antennae., [ES] Se presenta el tercer ejemplar del trilobites asáfido Megistaspis (Ekeraspis) cf. hammondi con Conservación excepcional de apéndices, procedente del Fossil-Lagerstätte ordovícico de tipo Burgess Shale más importante del mundo, localizado en Marruecos. Los trilobites con apéndices o partes blandas se detectan en niveles del Tremadociense superior dentro de la Formación de Fezouata, pero son fósiles muy raros. El ejemplar estudiado conserva la antena derecha y nueve apéndices situados bajo el exoesqueleto, localizados en la parte derecha del cuerpo. Se trata principalmente de endópodos, pero al menos en dos apéndices se reconocen partes de los exópodos porque conservan sus largas lamelas. El primer endópodo parece corresponder al extremo distal del tercer apéndice cefálico, y el resto son apéndices torácicos. Las antenas observadas en ejemplares comerciales de la misma especie suelen estar manipuladas por los preparadores y son poco fiables. Además del asáfido estudiado, la conservación de partes blandas y apéndices se conoce en otras cuatro especies coetáneas, totalizando medio centenar de ejemplares publicados. Pero es muy posible que existan muchos más casos en los que los apéndices de aquellos ejemplares que conserven las antenas permanezcan en realidad ocultos bajo el caparazón dorsal., El presente trabajo es una contribución a los proyectos CGL2017-87631-P del MICINN y 735 del PICG (IUGS-UNESCO), habiendo recibido financiación en especie de la empresa Jurassic Dreams (Alicante). AAS es beneficiario de fondos de investigación portugueses de la FCT – Fundação para a Ciência e Tecnologia, I.P. (ref. UIDB/00073/2020), en el ámbito de la Unidad de I&D Centro de Geociências (CGEO).

Se presenta la primera cita de un graptolito dendroideo en el Devónico de la Cordillera Cantábrica, que a su vez constituye el primer hallazgo de graptolitos bentónicos en materiales de este periodo del suroeste de Europa. El horizonte estudiado se sitúa cerca del techo de la Formación Moniello-Santa Lucía y se asigna al Eifeliense inferior por medio de conodontos y braquiópodos. Los graptolitos conservan parte de su peridermo orgánico y relieve original, fosilizados en margas, pero se hallan fragmentados. El estudio taxonómico permite adscribirlos a la nueva especie Dictyonema georgii sp. nov., caracterizada por una malla de aspecto desmográptido marcada por el desarrollo irregular de algunos estipes a partir de las dicotomías y, sobre todo, por la existencia de puentes tecales con distintas orientaciones y grosores, parte de los cuales son tan anchos como los estipes e implican transferencias de grupos tecales entre estipes adyacentes. Además, la nueva especie se diferencia de las escasas formas comparables por sus estipes más finos y numerosos, The first record of a Devonian graptolite from the Paleozoic of the Cantabrian Mountains is here reported, also being the first occurrence of benthic graptolites for this period in southwestern Europe. The studied horizon is located near the top of the Moniello-Santa Lucía Formation and has been assigned to the lower Eifelian by means of conodonts and brachiopods. The graptolites retain part of their organic periderm and partial relief, being fragmented and preserved in marls. The taxonomic study revealed a new species Dictyonema georgii sp. nov., characterized by a desmograptid-like mesh (without pseudoanastomosis) marked by the irregular development of some stipes from dichotomies and, above all, by the existence of irregularly oriented thecal bridges; these have different thicknesses, some being as wide as the stipes, and implying thecal transfer between adjacent stipes. Furthermore, the new species differs from the few comparable forms by its thinner and relatively more numerous stipes

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)

Se presenta la primera cita de un graptolito dendroideo en el Devónico de la Cordillera Cantábrica, que a su vez constituye el primer hallazgo de graptolitos bentónicos en materiales de este periodo del suroeste de Europa. El horizonte estudiado se sitúa cerca del techo de la Formación Moniello-Santa Lucía y se asigna al Eifeliense inferior por medio de conodontos y braquiópodos. Los graptolitos conservan parte de su peridermo orgánico y relieve original, fosilizados en margas, pero se hallan fragmentados. El estudio taxonómico permite adscribirlos a la nueva especie Dictyonema georgii sp. nov., caracterizada por una malla de aspecto desmográptido marcada por el desarrollo irregular de algunos estipes a partir de las dicotomías y, sobre todo, por la existencia de puentes tecales con distintas orientaciones y grosores, parte de los cuales son tan anchos como los estipes e implican transferencias de grupos tecales entre estipes adyacentes. Además, la nueva especie se diferencia de las escasas formas comparables por sus estipes más finos y numerosos The first record of a Devonian graptolite from the Paleozoic of the Cantabrian Mountains is here reported, also being the first occurrence of benthic graptolites for this period in southwestern Europe. The studied horizon is located near the top of the Moniello-Santa Lucía Formation and has been assigned to the lower Eifelian by means of conodonts and brachiopods. The graptolites retain part of their organic periderm and partial relief, being fragmented and preserved in marls. The taxonomic study revealed a new species Dictyonema georgii sp. nov., characterized by a desmograptid-like mesh (without pseudoanastomosis) marked by the irregular development of some stipes from dichotomies and, above all, by the existence of irregularly oriented thecal bridges; these have different thicknesses, some being as wide as the stipes, and implying thecal transfer between adjacent stipes. Furthermore, the new species differs from the few comparable forms by its thinner and relatively more numerous stipes

[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

El primer hallazgo de graptolitos ordovícicos en el sinclinal de Rececende (Dominio del Manto de Mondoñedo, NO de España) permite reinterpretar la sucesión estratigráfíca del área. La asociación de graptolitos incluye dos especies diferentes de didymográptidos extensiformes, comparables con varias especies del Darriwiliense, claramente anteriores a la Biozona de D. murchisoni. Este registro en una sección continua, en la que está ausente la principal capa de hierros sedimentarios de las Pizarras de Luarca (s.l.) en esta región, permite plantear la posibilid ad de que las denominadas "capas de Strophomenas " y la “capa Rececende"sean en realidad una única capa fosilrfera de edad Ordovícico Superior. La correlación de detalle entre las distintas unidades del Ordovícico dentro del Manto de Mondoñedo debe ser modificada con respecto a interpretaciones previas, que requieren ser revisadas con nuevos datos paleontológicos, First record of Ordovician graptolites in the Rececende Syncline (Mondohedo Nappe Domain, N W Spain ) allows a new interpretation of the stratigraphic succession in the area. The graptolite assemblage includes two different extensiform didymograptids which bear some resemblance with diverse Darriwilian-like forms, all of them clearly older than the D. muchiso ni graptolite Biozone. They occur in a continuous section lacking the main ironstone bed known from the Luarca Shales (s.l.) on this region, opening the possibility that the previously defined "Strophomena's beds" and the “Rececende bed" on this syncline could in fact represent the same Upper Ordovician fossiliferous bed. Detailed correlation between Ordovician formations across the Mondonedo Nappe needs to be modified with regards to the previous stratigraphic interpretations, which need to be reviewed with new paleontological data

Se presenta la historia poco conocida de los fósiles encontrados en el interior de las minas de Almadén desde mediados del siglo XIX, y cómo éstos influyeron en el conocimiento y datación de los materiales geológicos que conforman el yacimiento de mercurio. El registro paleontológico se desglosa en un icnofósil ordovícico procedente de un bloque englobado en la llamada “piedra frailesca” (una brecha volcánica básica que rellena diatremas), y en diversos graptolitos y otros invertebrados del Silúrico temprano conservados en pizarras negras, uno de los cuales - Parapetalolithus hispanicus (Haberfelner, 1931)- tiene su estratotipo en el piso 12 de la mina principal.

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.

Se presenta el primer registro español de Phycodes noha Mikuláš, un sistema horizontal de galerías en disposición flabelliforme, restringida a las facies lutíticas del Ordovícico Inferior de la República Checa y del Ordovícico Medio de la Península Ibérica. Los ejemplares españoles proceden de las pizarras del Oretaniense inferior (Darriwiliense medio basal) de la sección de la Cuesta de Valderuelo, al oeste de Navas de Estena (Ciudad Real). El análisis morfológico permite considerar a Phycodes canelensis, definido en el Oretaniense inferior de Portugal, como un sinónimo posterior de P. noha. El descubrimiento de este icnofósil incrementa la escasa icnodiversidad conocida en el Ordovícico Medio centroibérico.

La nuevas divisiones de la escala global del Sistema Ordovícico, con excepción de los pisos Tremadociense e Hirnantiense, son difíciles de aplicar en la Península Ibérica, pues sus estratotipos de límite radican en facies y faunas de aguas profundas, desconocidas en las plataformas someras y de paleolatitud elevada del ámbito peri-gondwánico. Antes de ello, la escala regional británico-avalónica fue utilizada en Iberia durante todo el siglo XX, pero presenta serios inconvenientes de correlación vinculados con la propia evolución, conceptual y de criterio, registrada en las áreas tipo británicas durante los últimos 40 años. Sin embargo, la escala regional bohemo-ibérica es la que actualmente aporta una mayor precisión a las correlaciones, pues se basa en elementos bioestratigráficos y biocronológicos de distribución común a todo el margen peri-gondwánico europeo y norteafricano, y la que mantiene vínculos episódicos con otras escalas regionales, que permitirán resolver progresivamente las equivalencias con la escala global.

Lostelefínidos espipelágicos son trilobites raros en Sudamérica, donde se conocen pocos ejemplares en elOrdovícico de la Precordillera, la cuenca de Famatina, la Puna oriental y la Cordillera Oriental argentina. En este trabajo se presentan los registros más septentrionales de los géneros Carolinites y Oopsites. El Ordovícico Inferior de la cuenca andina central, procedentes de la Formación Sella del sur de Bolivia(Carolinites genacinaca Ross s.l.) y de la Formación San José del suroeste del Perú (Oopsites sp. nov). El exiguo registro de estos telefínidos se halla vinculado con corrientes de aguas cálidas,que esporádicamente se dirigían hacia el sur a lo largo de lmargen gondwánico, transportando trilobites paleotropicales hacia paleolatitudes más elevadas con aguas templadas a frías. Epipelagic telephinid trilobites rarely occur in the Ordovician of South America, being represented byfew specimens recorded from the ArgentinianPrecordillera, the Famatina Basin, eastern Puna and Cordillera Oriental. We here report the northernmost occurrences of the genera Carolinites and Oopsites in the Central Andean Basin, coming from the Lower Ordovician rocks of the Sella Formation of southern Bolivia (Carolinites genacinaca Ross s.l.) and from the San José Formation of southwestern Peru (Oopsites sp.nov). The scarce record of these telephinids has been related to warm water currents, that sporadically moving southwards along the Gondwanan margin,carrying palaeotropical trilobites into more temperate to cool-­‐water higher palaeolatitudes. Fil: Gutierrez Marco, Juan Carlos. Consejo Superior de Investigaciones Científicas; España Fil: Rábano, Isabel. Museo Geominero; España Fil: Aceñolaza, Guillermo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina Fil: Chacaltana, César. INGEMMET; Perú

p. 209-288 Spain contains some of the most extensive and fossiliferous Palaeozoic outcrops in Europe, including echinoderm faunas that are internationally signpalaificant in terms of systematics, paleoecology and palaeobiogeography. This field trip will review some of the most remarkable Palaeozoic localities in North Spain. It will be divided into two different but related geological and geographical areas, the Cantabrian Zone in northern Spain and its southeastern prolongation, known as the Iberian Chains SI

Ordovician cephalopods from the Valongo Formation are among the first Ordovician fossils described from the Iberian Peninsula. The present review shows a lower taxonomical diversity than previously reported. Large endocerids and orthocerids are abundant in beds of early Oretanian (Middle Darriwilian) age, and orthocerids and some tarphycerids occur in strata of early Dobrotivian (Late Darriwilian) age. Despite the poor preservation in shales and the absence of internal structures, five different forms of longicones were identified, remaining them in open nomenclature. Tarphycerids are better recognizable and belong to the late Darriwilian forms Trocholites fugax and T. cf. depressus, with the former species recorded over a wide area of Ibero-Armorica and Bohemia, and the second related to a Baltic form. The occurrence of the genus Trocholites among Circumpolar Gondwana cephalopod faunas is consistent with the sporadic transfer of warm to temperate water masses southwards from the vicinity of Baltica, through a period of climatic disturbances affecting the southern hemisphere during the late Darriwilian

Ordovician cephalopods from the Valongo Formation are among the first Ordovician fossils described from the Iberian Peninsula. The present review shows a lower taxonomical diversity than previously reported. Large endocerids and orthocerids are abundant in beds of early Oretanian (Middle Darriwilian) age, and orthocerids and some tarphycerids occur in strata of early Dobrotivian (Late Darriwilian) age. Despite the poor preservation in shales and the absence of internal structures, five different forms of longicones were identified, remaining them in open nomenclature. Tarphycerids are better recognizable and belong to the late Darriwilian forms Trocholites fugax and T. cf. depressus, with the former species recorded over a wide area of Ibero-Armorica and Bohemia, and the second related to a Baltic form. The occurrence of the genus Trocholites among Circumpolar Gondwana cephalopod faunas is consistent with the sporadic transfer of warm to temperate water masses southwards from the vicinity of Baltica, through a period of climatic disturbances affecting the southern hemisphere during the late Darriwilian

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

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

Preliminary studies of some stratigraphic sections spanning the Ordovician-Silurian boundary in the southern Cantabrian Zone (Iberian Massif, NW Spain) demonstrate the existence of a record of Hirnantian glaciomarine diamictites and shallow-water quartzites in at least three localities, situated in the Bodón nappe. These rocks, evidenced for the first time in the Cantabrian Zone, are probably related to the infilling of a paleorelief, scoured in the Barrios Formation during the Late Ordovician glaciation. The occurrence of an ubiquitous quartzite unit, generally related to the Ordovician-Silurian boundary in most parts of northern Gondwana, is now extended to the outcrops here analyzed. The Hirnantian quarzite probably occurs in additional areas of the Bodón and Correcilla nappes, where its location and significance might be underestimated, and described as the uppermost part of the Barrios Formation (Middle Cambrian to Arenigian). The same quartzite is probably recognized in the areas with volcanic necks within the Barrios Formation, and also in its stratotype, in which a latest Ordovician/earliest Silurian quartzite overlies unconformably on Middle Ordovician shales

A Silurian fossil has been collected from sandstone pebbles in the red Cenozoic deposits of the famous Roman gold-mine of Las Médulas. It consists on an articulated shell of the cardiolid bivalve Cardiola gibbosa Barrande, of basal Gorstian age (Ludlow). This species is considered as an exotic element to the neighboring Paleozoic outcrops, being most probably reworked from an unknown area souther of the Ollo de Sapo anticlinorium. This hypothesis agrees with the recent geological reinterpretation of the goldbearing units as a system of Paleogene fluvial terraces. The fossiliferous pebble is attributed to the third terrace scoured by an ancient river flowing to the NE, being progressively entrenched during the initial stages of the Alpine convergence which ends with the formation of the compressive El Bierzo Cenozoic basin

A Silurian fossil has been collected from sandstone pebbles in the red Cenozoic deposits of the famous Roman gold-mine of Las Médulas. It consists on an articulated shell of the cardiolid bivalve Cardiola gibbosa Barrande, of basal Gorstian age (Ludlow). This species is considered as an exotic element to the neighboring Paleozoic outcrops, being most probably reworked from an unknown area souther of the Ollo de Sapo anticlinorium. This hypothesis agrees with the recent geological reinterpretation of the goldbearing units as a system of Paleogene fluvial terraces. The fossiliferous pebble is attributed to the third terrace scoured by an ancient river flowing to the NE, being progressively entrenched during the initial stages of the Alpine convergence which ends with the formation of the compressive El Bierzo Cenozoic basin

Se describe una asociación singular de grandes obólidos, procedente de la parte basal de la “Formación Cuarcítica” de la Serra de Marão (N Portugal), correlacionable con la Cuarcita Armoricana de otras regiones centroibéricas. A pesar de que la mayor parte de los ejemplares están mal conservados y acusan deformación tectónica, se han podido identificar cuatro taxones diferentes que son descritos en nomenclatura abierta: Lingulobolus sp. [próximo a L. hawkei (Rouault)], Ectenoglossa cf. lesueuri (Rouault), “Lingulella” sp., y un obólido indeterminable de ornamentación divaricada (tal vez relacionado con Libecovicella). Esta asociación se adscribe a la biofacies de obólidos gigantes que caracteriza los ambientes epicratónicos de aguas someras en multitud de localidades perigondwánicas de Europa y el norte de África. La especie “Lingulella” major Teixeira, Ribeiro & Silva, descrita con anterioridad en los mismos afloramientos aquí estudiados, también ha sido revisada taxonómicamente, proponiéndose que quede restringida al lectotipo aquí designado, el cual tiene probablemente una edad ordovícica. Del mismo modo se analizan las citas de braquiópodos inarticulados en la Formación Desejosa (anteordovícico), descartándose la presencia de “Lingulella” montana Fenton & Fenton, recogida en las últimas síntesis internacionales del Ordovícico portugués. Por último, se aporta un esquema estratigráfico general de las formaciones ordovícicas en la Serra do Marão, invalidando el llamado “Miembro de Sejarão” citado en la parte inferior de la Cuarcita Armoricana, al tiempo que se presenta una breve actualización y revisión del registro paleontológico del Ordovícico de la región.

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

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

Se describen diversas estructuras discoidales a subcónicas, cementadas a restos esqueléticos de braquiópodos, moluscos, trilobites y cistideos. que constituyen los primeros elementos de fijación de pelmatozoos a sustratos firmes encontrados en el Ordovícico Medio de la Zona Centroibérica del Macizo Hespérico. El material proviene de cinco localidades de edad comprendida entre el Oretaniense inferior y el Dobrotiviense superior, y ha sido asignado a los morfogéneros Podolithus y Lichenocrinus?, el primero de los cuales se conocía previamente en las calizas del Ashgill de la Rama Aragonesa de la Cordillera Ibérica. Los ejemplares de Podolithus encontrados en las Capas con Tristani pertenecen al menos a dos morfoespecies distintas, tratadas en nomenclatura abierta, que sc diferencian por sus caracteres morfológicos y los fragmentos pluricolumnales asociados. [ABSTRACT] Pelmatozoan holdfasts, in Ihe form of discoid to subeonical multiplated structures, have been observed attached to shelly fragments ol articulate brachiopods. molluscs, trilobites and cystoids from five localities of the Central Iberian Zone of the Hesperian Massif. The described material ranges from lower Oretanian to upper Dobrotivian in age, and represents the first evidence of hard substrate colonization by echinoderms in the Middle Ordovician of Spain. The identified taxa belong to the morphogenera Podolithus and ?Lichenocrinus, the former also recorded from Ashgill limestones in the eastern Iberian Cordillera. At least two morphospecies of Podolithus, which have been left in open nomenclature, are distinguished on the basis of their overall morphology and stem characteristies.

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)

The type specimen ofthe Lower Cambrian (Bilbilian) trilobite «Ellipsocephalus pradoanus» Verneuil & Barrande, 1855 is redescribed and illustrated. It is stored in the Verneuil collection ofthe Claude-Bernard University at Lyon (France). By means of the cranidial characteristics it has been doubtfully related with the genus Realaspis, and the poor preservation of the lectotype of R. ? pradoanus supports the restriction of the species to this unique specimen

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 type specimen ofthe Lower Cambrian (Bilbilian) trilobite «Ellipsocephalus pradoanus» Verneuil & Barrande, 1855 is redescribed and illustrated. It is stored in the Verneuil collection ofthe Claude-Bernard University at Lyon (France). By means of the cranidial characteristics it has been doubtfully related with the genus Realaspis, and the poor preservation of the lectotype of R. ? pradoanus supports the restriction of the species to this unique specimen

The first Silurian graptolites from NW Spain were discovered South of Brazuelo de Pradorrey (province of León) by Casiano de Prado in 1855. The locality lies in the core of the Castrillo syndine, where the Silurian succession is composed by a lower unit of ?Rhuddanian-Aeronian sandstones, gradually passing to an upper unit of black graptolitic shales. Aeronian graptolites (?D. triangulatus and D. convolutus biozones) were reported from the top of the sandy formation and from the transitional beds in the lower half of the overlying unit. The Brazuelo locality corresponds to the younger black shales, and includes three sucessive horizons with Telychian graptolites. The first one represents the upper part of the R. linnaei Biozone, followed up in the section by a second assemblage, which probably belongs to the M. griestoniensis 3¡ozone, and finally, by a third horizon also representative of the M. griestonensis or even the T. tulibergi Biozone. Craptolite assemblages are poor and bad preserved, but include some species of high palaeobiogeographic and palaeoenvironmental significance, as for instance Metaclimacograptus cf. asejradi Legrand or Paraclimacograptus? flamandi (Legrand), typical of shallow sapropelitic facies in peri- and intracratonic Gondwanan basins

The first Silurian graptolites from NW Spain were discovered South of Brazuelo de Pradorrey (province of León) by Casiano de Prado in 1855. The locality lies in the core of the Castrillo syndine, where the Silurian succession is composed by a lower unit of ?Rhuddanian-Aeronian sandstones, gradually passing to an upper unit of black graptolitic shales. Aeronian graptolites (?D. triangulatus and D. convolutus biozones) were reported from the top of the sandy formation and from the transitional beds in the lower half of the overlying unit. The Brazuelo locality corresponds to the younger black shales, and includes three sucessive horizons with Telychian graptolites. The first one represents the upper part of the R. linnaei Biozone, followed up in the section by a second assemblage, which probably belongs to the M. griestoniensis 3¡ozone, and finally, by a third horizon also representative of the M. griestonensis or even the T. tulibergi Biozone. Craptolite assemblages are poor and bad preserved, but include some species of high palaeobiogeographic and palaeoenvironmental significance, as for instance Metaclimacograptus cf. asejradi Legrand or Paraclimacograptus? flamandi (Legrand), typical of shallow sapropelitic facies in peri- and intracratonic Gondwanan basins

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

A new continuous section with Aeronian to lower Telychian graptolites is described near Corral de Calatrava (province of Ciudad Real). The transition between the «Criadero Quartzite» and the overlying black shales is detailed. The section is correlated with another similar sucessions around the Ordovician/ Silurian boundary in the southern part of the Central Iberian Zone, and chronostratigraphic aspects are briefly analyzed and discussed. The sedimentation of the «Criadero Quartzite» took place during Rhuddanian to late Aeronian times; a minor hiatus was developed at the upper limit with the graptolitic black shales. The base of the latter is not older than the palmeus sub-biozone of the early Telychian

Two new fossil localities yielding graptolites of the, (undgreni and leintwardinensis biozones (early Homerian and basal Lùdfordiàn, respectively) are studied from the Al an gè region, which lies on the southernmost part of the Central Iberian Zone, Previous mentions to graptolites from a nearby outcrop were also reviewed and the original specimens reassigned to some earlier horizons in the Wenjock AH these data confirm the presence of Silurian rocks over a region very imprecisely known in terms of Paleozoic sedimentary geology and paleogeograppy

Torrubia (1754) was the first to describe the presence of nodules in the Silurian black shales cropping out in the old tile works near El Pobo de Dueñas in the province of Guadalajara. He called them «geode-stones» reminiscent to «little cakes and diceboxes», considering them as petrefacts of nonorgan ic origin. The presence of nodules in Silurian graptolite facies in several i be rían localities is also briefly examined, and the diverse popular interpretations of these structures in the country are also annotated (i.e. «moorish heads», mammut-coprdlites, turtles or even «copro/ithus neanderthalensis»