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The Spanish Courel Mountains UNESCO Global Geopark has strong educational and touristic resources despite limited preservation of Paleozoic invertebrate fossil assemblages within metamorphic rocks. The paleontological sites are managed by means of their inventory and integration in a Geographical Information System, the construction of virtual 3D fossil models, the creation of a fossil collection exhibition, the transport of large boulders with fossils to places such as tourist offices, and hiking trails to see ichnofossils. To enable geoconservation, the Palaeozoic paleontological sites are neither promoted nor frequently visited. Fossils found in the Geopark by paleontologists and fortuitously by local people or hikers are deposited and safeguarded in the Geological Museum and are available for eventual exhibition and paleontological studies.

International audience

More than 30 species of tergomyan, gastropod, bivalve and cephalopod molluscs are described from the Late Ordovician of central and eastern Anti-Atlas, Morocco. For the cephalopods this represents the first systematically known taxa of the region. Tergomyans and gastropods are most common in the more shaly part of the Lower Ktaoua Formation, while bivalves are more frequent in the sandy part of the Lower Second Bani Formation. A southern Gondwana aspect is evident for the tergomyan, gastropod and bivalve assemblages, sharing many taxa with Bohemia, while no clear signal is present for the cephalopods. The latter reflects insufficient knowledge of the fauna of large parts of these areas. The widely recognized Holopea? antiquata is transferred to the genus Radvanospira gen. nov.; other new gastropod taxa include Allossospira gen. nov., Tritonophon grandis sp. nov., Radvanospira baniensis sp. nov. and Lophospira latilabra sp. nov. Most of the diverse bivalve fauna and the few cephalopods are left in open nomenclature but new taxa include the bivalve Praenucula pojetai sp. nov. and the cephalopods Wadema tattai sp. nov. and Tafadnatoceras tiouririnense gen. et. sp. nov. The Late Ordovician bivalves from Morocco are dominated by pteriomorphs and protobranchs, inhabiting infaunal, semi-infaunal and epifaunal niches.

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).

International audience

The Palaeozoic succession of the Sierra Norte de Sevilla UNESCO Global Geopark (Ossa Morena Zone of the Iberian Massif, SW Spain) includes a nearly complete Silurian succession, ca. 150 m in thickness, deposited in outer shelf settings. Among sections explored along the western end of the El Pintado reservoir, in the core part of the Valle syncline, the El Pintado-1 section exhibits graptolite rich Silurian black-shale facies ranging from the base of the Rhuddanian to the upper Ludfordian. Most of the standard graptolite biozones of the Silurian System have been identified in this succession, and high-resolution biostratigraphical studies have led to the unanimous candidacy of this section as replacement GSSP for the base of the Telychian Stage by the International Subcommission on Silurian Stratigraphy. The preliminary record of Llandovery graptolites in the lower part of the succession so far comprises more than 200 species, 19 of them new. Graptolites from the upper Telychian and from the remaining part of the Silurian succession have not yet been studied in detail. The condensed, almost entirely graptolitic black shale Silurian succession of the El Pintado-1 geosite is of enormous value for the world’s palaeontological heritage, reinforced by the future placement here of the GSSP for the base of the Telychian Stage. Due to its fragility and exclusively scientific nature, the section is not open to public visitors of the Geopark, and its difficult accessibility also adds some protection to this internationally important geosite, favouring its conservation beyond the regional legislative framework.

The Paleozoic succession in the Nevera inlier of the Molina-Alto Tajo UNESCO Global Geopark (Western Iberian Cordillera, NE Spain) includes an incomplete, richly fossiliferous Silurian succession, ca. 350‒400 m thick, at the locality of Checa, one of the geosites of international interest in the Paleozoic of Spain. The Checa section starts with quartzites (Los Puertos Formation: Rhuddanian to Aeronian) which rest unconformably on Late Ordovician glaciomarine diamictites (Orea Formation: Hirnantian) and are succeeded by graptolitic black shales (Bádenas Formation). The basal 60 m of the latter unit are of Telychian age and exhibit rich graptolite faunas of nine successive graptolite biozones and subzones, with more than 85 graptolite species identified of which four were new. Besides the scientific value of the fossil locality for paleontology and international correlation of the early Silurian, aspects of the promotion and preservation of its geological heritage have been enhanced by designation as a national and international geosite, as well as by the integration in a geo-trail for visitors to the park and the fencing of part of the fossil locality to avoid illegal digging and collecting.

The giant Ordovician trilobites from the Canelas quarry constitute the most iconic sign of identity of the Arouca UNESCO Global Geopark at an international level. Palaeontological studies determined the importance of this fossil locality for studying aspects of the social behavior of these marine arthropods and their interactions with other represented invertebrate fossil groups. Although part of the famous ‘gigantism’ of the fossils represented in the slate quarry is due to tectonic expansion, which is responsible for one-third of the outstanding size of the fossils, there is no doubt that this locality, sometimes considered as a fossil lagerstätte, has a great scientific interest and represents a unique international reference among the geological heritage of Portugal. The construction of an on-site museum and the establishment of a geotrail around the quarry have turned this geosite into an example of cooperation between extractive industry, education, science and sustainable development. The formal partnership established with the AGA – Arouca Geopark Association reinforces the projection of this geosite, allowing its disclosure in exhibitions and educational programs, as well as the collaboration with the scientific community., Departamento de Geologia, Universidade de Trás-os-Montes e Alto Douro, Portugal, Centro de Geociências, Universidade de Coimbra, Portugal, Instituto Geológico y Minero de España, España, Instituto de Geociencias, Consejo Superior de Investigaciones Científicas, España, Instituto de Geociencias, Universidad Complutense de Madrid, España, Área de Paleontología, Universidad Complutense de Madrid, España

El Macizo de Aragoncillo, fue testigo del descubrimiento, hace más de 250 años, de los primeros trilobites encontrados en la península Ibérica. Pero más allá de algunas citas posteriores de especies ordovícicas en los siglos XIX y XX, el grupo nunca ha sido objeto de estudios o descripciones paleontológicas locales. En este trabajo se revisan los datos precedentes y se señalan once yacimientos paleontológicos con trilobites, localizados en la parte alta de la Formación Villar del Saz. La asociación estudiada comprende 14 especies, pertenecientes a 13 géneros. Entre los resultados taxonómicos, se presentan los primeros hallazgos ibéricos del facópido Zeliszkella lapeyrei (Bureau), hasta ahora restringido al Macizo Armoricano francés, en tanto que el calimenáceo Colpocoryphe grandis (Šnajdr) es detectado por vez primera en niveles españoles del Dobrotiviense. Desde el punto de vista bioestratigráfico, la asociación de trilobites se asigna a la parte alta de la Biozona de Placoparia borni del Dobrotiviense superior, que en este caso equivale al Sandbiense inferior por su coetaneidad con graptolitos de la Biozona de Nemagraptus gracilis. Es por ello que la presencia de Neseuretus tristani (Brongniart) en el Ordovícico Superior constituye una de las contadas evidencias mundiales del género Neseuretus previo a su extinción.

The Anti-Atlas contains a thick, volcanic-free Ordovician succession that originally deposited in a passive-margin basin. Three main sedimentary packages are bounded by major unconformities: (i) the Tremadocian–Floian Lower Fezouata and Upper Fezouata formations, which unconformably overlie a palaeorelief of Cambrian rifting volcanosedimentary complexes, and are subsequently topped by a Dapingian para-conformable gap; (ii) the Darriwilian–Katian Tachilla Formation and First Bani and Ktaoua groups, the latter unconformably overlain by a Hirnantian glaciogenic succession; and (iii) the Second Bani Group, which subsequently infilled the former glaciogenic palaeorelief. Due to the scarcity of carbonate interbeds for etching analyses, leading to rare references of conodonts, the global Ordovician chart is interpolated on the basis of microphytoplancton (acritarchs and chitinozoans), regional graptolites and brachiopods. The Ordovician counter-clockwise rotation of Gondwana led its Moroccan margin from mid-to high-latitude positions, leading to the onset of a siliciclastic, wave-and storm-dominated platform. Flooding surfaces are marked by shelly silty carbonate interbeds that reflect the episodic development of echinoderm–bryozoan meadows during Katian times; in areas protected from siliciclastic input, they reached massive and bedded bioaccumulations (Khabt-el-Hajar Formation). The Hirnantian glaciation controlled the incision of numerous tunnel channels, infilled with both alluvial to fluvial sediments and glaciomarine diamictites. The Hirnantian palaeorelief was definitively sealed during Silurian times., The authors thanks the useful and detailed revisions made by J. Colmenar, T. Servais and one 661 anonymous referee. This work is dedicated to the memory of Jacques Destombes who left us 662 during the redaction of this synthesis.This paper is a contribution to Spanish project CGL2017-663 19 87631-P from Spanish Ministry of Science, Innovation and Universities and IGCP 653 (IUGS-664 UNESCO) project ‘The Onset of the Great Ordovician Biodiversification Event’.

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