150 years of the discovery of the Cambrian Lagerstätte of Murero (Cadenas Ibéricas, NE Spain)

El yacimiento paleontológico del Cámbrico inferior-medio de Murero (Cadenas Ibéricas, NE de España) es una localidad clásica del Cámbrico europeo. Fue dado a conocer a la ciencia por Edouard de Verneuil en 1862, celebrándose en 2012 el 150 aniversario de su descubrimiento. Es un siglo y medio de trabajos geológicos y de logros puestos al servicio del conocimiento del Período Cámbrico. Murero es un Lagerstätte excepcional porque coexisten en él grupos esqueléticos y de cuerpo blando a lo largo de un registro estratigráfico continuo que abarca unos 8 millones de años, dividido en 14 zonas de trilobites. En 1997, este yacimiento paleontológico fue el primero de España en obtener de la Administ…

The Leonian Stage (early Middle Cambrian): a unit for Cambrian correlation in the Mediterranean subprovince

The Leonian (early Middle Cambrian) regional Stage of Iberia is revised from a lithostratigraphic and biostratigraphic point of view in order to propose it as a chronostratigraphic unit for the Mediterranean subprovince (outcrops in Spain, France, Italy, Germany, Morocco and Turkey). This revision now permits a correlation of the Leonian Stage with the other early Middle Cambrian regional Stages. For this correlation the first appearance datum (FAD) of Eoparadoxides mureroensis, Macannaia spp., Schistocephalus antiquus and Oryctocara granulata are employed for the lower boundary; while the FADs of Badulesia tenera, Ctenocephalus (Hartella) spp., Parasolenopleura aculeata and Triplagnostus g…

Trace and soft body fossils from the Pedroche Formation (Ovetian, Lower Cambrian of the Sierra de Córdoba, S Spain) and their relation to the Pedroche event

The low Lower Cambrian rocks from the Sierra de Cordoba contain one of the best successions in Europe, which consists of well exposed mixed facies with abundant fossil assemblages showing long stratigraphical ranges throughout the Pedroche Formation. These assemblages include diverse Ovetian archaeocyaths, trilobites, small shelly fossils, calcimicrobes, trace fossils and stromatolites. Trace fossils are still poorly known, and thus they are the main objective of this work. Ichnological data are obtained from the Arroyo de Pedroche 1, Arroyo de Pedroche 2 and Puente de Hierro sections. Trace fossils include the ichnogenera Bergaueria, aff. Bilinichnus, Cochlichnus, aff. Cosmorhaphe?, Cylind…

Upper Ovetian trilobites from Spain and their implications for the palaeobiogeography and correlation of the Cambrian Stage 3 in Gondwana

Abstract The upper part of the La Herreria Formation in Los Barrios de Luna (Leon Province, N Spain) has been revised from a palaeontological and biostratigraphical point of view. Two stratigraphic sections have been studied including their trilobite and ichnofossils contents. The ichnofossil assemblages have a high diversity of species characterising the Cruziana ichnofacies, suggesting a shallow sublittoral environment for the upper part of the La Herreria Formation. The trilobites species recognised are Lunagraulos antiquus , Dolerolenus formosus , Dolerolenus longioculatus , Lunolenus lunae , Metadoxides richterorum , Metadoxides armatus and Sardaspis ? sp. from the upper Ovetian (lower…

Proposal of a reference section and point for the Cambrian Series 2-3 boundary in the Mediterranean subprovince in Murero (NE Spain) and its intercontinental correlation

The classical lower-middle Cambrian boundary is approximately equivalent with the boundary of the Cambrian Series 2 and 3, which is now in the process of definition by the International Subcommission on Cambrian Stratigraphy. Currently, there are two oryctocephalid trilobite species first appearance data (FAD) that are suggested as possible markers of this level: Ovatoryctocara granulata Tchernysheva, 1962 and Oryctocephalus indicus (Reed, 1910), respectively. Until now neither of these two species has been recorded in the Mediterranean subprovince or Baltica. As a result, in these regions a level potentially correlating with either the FAD of Ovatoryctocara granulata or Oryctocephalus indi…

ParadoxidesbrachyrhachisLinnarsson, 1883 versusParadoxidesmediterraneusPompeckj, 1901: a problematic determination

A revision of paradoxidid trilobites reveals that previous identifications of specimens from Sardinia and Spain as the Nordic trilobite species Paradoxides brachyrhachis Linnarsson, 1883, are mistaken. The southern species, occurring also in France, is here referred to Eccaparadoxides mediterraneus (Pompeckj, 1901). Main differences are seen in the preocular field, pleural furrow and pygidium. The species P. brachyrhachis is referred with question to the genus Mawddachites Fletcher 2007.

New bradorid arthropods from the Lower Cambrian of Spain

Lower Early Cambrian rocks of the Pedroche Formation in the Sierra de Cordoba consist of well-exposed mixed facies with abundant fossil assemblages showing long stratigraphical ranges. These assemblages include diverse Ovetian archaeocyaths, trilobites, small shelly fossils, calcimicrobia, trace fossils, and stromatolites. For the ostracod-like Cambriidae it is the first record from the Iberian Peninsula. Cordubiella pedrochensis n.gen. n.sp. comes from two sections of the lower Pedroche Formation: the Arroyo de Pedroche 1 sec- tion, and the Arroyo Pedroche 2 section. The material was collected in the zone of Lemdadella perejoni, of lower Ovetian age and below the Eoredlichia FAD. It supple…

Datos para la Historia de la Malacología Española: Las ediciones del <em>Catálogo</em> de Graells

Graells's contribution to the history of Malacology, his Catalogo de los Moluscos terrestes y de agua dulce observados en Espana y descripcion y notas de algunas especies nuevas o poco conocidas del mismo pais, is the first synthesis by a Spanish author on the subject dealing with the whole of continental Spain and the Balearic Islands. He described several new species, some of which have been included in the synonym of species known previously. The name of some of the species discussed has been abandoned, while for other cases his description remains valid.

Análisis criptopaleontológico del lapidario de Teofrasto (s. III a.C.)

The work “Perì líthon” or Teofrasto’s “Treatise of stones” has been considered the oldest text still available about minerals and rocks, even though it has remained incomplete. In this paper, the study of its contents shows that eleven of the stones called by geographic or cryptic names are either fossils from plants or vertebrates or chemical fossils. Therefore, the “Perì líthon” should also be considered as the oldest known treatise about palaeontology, because in addition to the fossils mentioned, it refers specifically to the fossilisation process.La obra “Perì líthon” o “Tratado de Piedras” de Teofrasto, es considerado el texto más antiguo conservado sobre minerales y rocas, aunque hay…

Bradoriid Arthropods from the Lower-Middle Cambrian of Scania, Sweden

Three species of bradoriid arthropods from the lower to middle Cambrian transitional interval of Scania, southern Sweden, are described and illustrated: Beyrichona tinea from the top of the traditional lower Cambrian (Gislov Formation; Ornamentaspis? linnarssoni Zone), and Hipponicharion eos and Alutella sp. from the basal portion of the traditional middle Cambrian (lowermost part of the Alum Shale Formation). The bradoriid fauna compares most closely with others previously described from western and eastern Avalonia (New Brunswick and England). The record of B. tinea suggests a correlation between the “Protolenus Zone” (Hupeolenus Zone) of western Avalonia and the O.? linnarssoni Zone of S…

Middle Cambrian Gogiid Echinoderms from Northeast Spain: Taxonomy, Palaeoecology, and Palaeogeographic Implications

Gogia parsleyi Zamora sp. nov. and Gogia sp. are described from two different echinoderm assemblages, both from the middle Cambrian of the Murero Formation (Iberian Chains, NE Spain). Gogia parsleyi is reconstructed and described on the basis of fifteen complete or partial specimens and numerous isolated plates. It is characterised by spiralled brachioles, simple epispires, sometimes covered by stereomic domes or tiny cover plates, and by thecal plates arranged in subregular circlets. This gogiid population comprises juveniles, advanced juveniles and mature individuals. The material was found in the upper part of the Murero Formation (upper Caesaraugustian—lower Languedocian). Gogia sp. is …

Recensión: Pelayo, F. 1999. Ciencia y Creencia en España durante el siglo XIX. La Paleontología en el debate sobre el Darwinismo. Cuadernos Galileo de Historia de la Ciencia, 20, Consejo Superior de Investigaciones Científicas, Madrid, 380 pp., ISBN 84-00-07849-7

Nos encontramos ante una nueva obra de Francisco Pelayo, quien en los últimos años viene realizando una interesante labor de análisis y caracterización histórica de la Paleontología española, adecuadamente enmarcada en la situación europea de esta ciencia. Este trabajo no es una continuación estricta del libro titulado Del Diluvio al Megaterio de este mismo autor (ver Noticias Paleontológicas 29), pero sí que existe cierta continuidad desde el punto de vista del análisis de las ideas paleontológicas en España.
 El título y subtítulo de la obra son suficientemente expresivos, mostrando claramente cuál va a ser el hilo conductor que se propone en la obra y que, de una manera precisa, es …

Systematic and biostratigraphy of the genera Parasolenopleura, Badulesia, and Pardailhania in the Iberian Chains: a useful zonation for the Miaolingian Series (former middle Cambrian) in the Mediterranean region

The trilobite species of three genera included in the Family Solenopleuridae: Parasolenopleura , Badulesia , and Pardailhania are revised. These genera have a great biostratigraphic interest due to their broad distribution in the Miaolingian Series (former middle Cambrian) of the Mediterranean Subprovince and because they constitute an evolutionary lineage, that facilitates an accurate regional correlation. Two of these genera ( Pardailhania and Badulesia ) have been used to define middle Cambrian zones in Spain (lower and middle Caesaraugustan, equivalent to the uppermost Wuliuan and the lower Drumian stages). Although, all authors have been using the same species to establish the Mediterr…

Recesión: Schroeder, R. & Perejón, A. (eds.) 2006. Contributions to the geology of Spain in memory of Prof. Franz Lotze. Zeitschrift der Deutschen Gesellschaft für Geowissenschaften

Recientemente se ha publicado un número especial en Memoria del Prof. Franz Lotze (1903-1971), editado por los doctores Rolf Schroeder (Frankfurt am Main) y Antonio Perejón (Madrid), consta de 12 contribuciones sobre distintas cuestiones geológicas de la Península Ibérica, a las que se añanden una interesante panorámica del trabajo geológico de Lotze en España, elaborado por los editores, y un sentido prólogo del Prof. Jaime Truyols (Oviedo).

El género Parabailiella Thoral, 1946 (Trilobita) en el Cámbrico Medio de las cadenas ibéricas (NE de España)

Se analiza el registro del género Parabailiella Thoral, 1946 en el Cámbrico medio de las Cadenas Ibéricas, al tiempo que se identifican y describen por primera vez en la región las cuatro especies que previamente se habían incluido en este género. La mayoría de las especies se encuentran registradas en varias secciones y las cuatro se han identificado en la sección Jarque 1. La distribución bioestratigráfica del género abarca desde el Leoniense medio hasta la base del Caesaraugustiense superior, lo que equivale en la escala propuesta por la International Subcommission on Cambrian Stratigraphy (ISCS) a la mayor parte del Piso 5 del Cámbrico y a la parte inferior del Piso Drumiense. La distri…

The first record ofDinesus(Trilobita, Dinesidae) in the Cambrian of the Mediterranean region

An important problem facing inter-regional correlation in the Cambrian is the scarcity of shared taxa between different palaeogeographic domains. Currently, species of the Corynexochida are proposed as tools to define the base of Cambrian Series 3. However, few Mediterranean Corynexochida species are known. A specimen of Dinesus truyolsi comb. nov. from the middle Cambrian of Spain represents the first record of this genus in the Acadobaltic province. Erbia and Tingyuania are accepted as junior subjective synonyms of Dinesus, and we now recognize 22 species within this genus. Dinesus has been found previously in lower to middle Cambrian strata of Australia, Russia, Kazakhstan, North America…

Bailiaspis (Trilobita) with English affinities from the Mansilla Formation (Cambrian Series 3 of the Iberian Chains; NE Spain)

A new study of the trilobite record in the Mansilla Formation (Iberian Chains, NE Spain) has led to the discovery of the presence of Bailiaspis aff. tuberculata, B. cf. tuberculata and Bailiaspis sp., the first certain citation of this genus in the Mediterranean subprovince. The age of the findings extends from Eccaparadoxides asturianus Zone (upper Leonian) to the lowermost Badulesia tenera Zone (lower Caesaraugustan), which correspond to the upper part of Stage 5 of Cambrian Series 3 and, probably, the lowermost Drumian. The specimens show the cranidial anterior border expanding backwards, forming a plectrum that is characteristic of Bailiaspis. The main characters of the three taxa inclu…

Challenges in defining the base of Cambrian Series 2 and Stage 3

Formal subdivision of the Cambrian System into four series and ten stages is in progress. The base of Cambrian Stage 3 (provisional), which is conterminous with the base of Cambrian Series 2 (provisional), is expected to be placed at a horizon close to the first appearance of trilobites, which marks the onset of the largest phase of the Cambrian explosion. Conceptually, an ideal boundary position would be marked by a significant and globally recognizable bioevent that divides the lower part of the Cambrian System into a sub-trilobitic Terreneuvian Series and a trilobite-dominated Series 2. If the level is to be identified principally through biostratigraphic means, its position also needs t…

Atopidae (Trilobita) in the upper Marianian (Cambrian Series 2, Stage 4) of Iberia

AbstractNew atopid trilobites are described from the early Cambrian Cumbres beds and Herrerías shale of northern Huelva Province (Andalusia, Spain) and are dated as middle–late Marianian (Cambrian Series 2, Stage 4). New specimens ofAtops calanusRichter and Richter, 1941 are described and the Laurentian speciesPseudatops reticulatus(Walcott, 1890b) is recognized for the first time in the Mediterranean subprovince. The associated trilobite assemblage studied herein suggests an age close to the base of Cambrian Stage 4.

OnCallavia(Trilobita) from the Cambrian Series 2 of Iberia with systematic status of the genus

Olenellid trilobites from the lower Cambrian of the Iberian Peninsula are very scarce and poorly studied, making them difficult to compare with defined species and to include in biostratigraphic and paleobiogeographic analyses. Based on newly collected specimens, we revise the species ‘Callavia? lotzei’ Richter and Richter, 1941 from the ‘Cumbres beds’ of Cumbres de San Bartolomé and the ‘Herrerías shale’ of Cañaveral de León, Sierra del Bujo, and Hinojales (Huelva, Spain), and ‘Paradoxides choffati’ Delgado, 1904 from the Vila Boim Formation of Elvas (Portugal). The new material indicates that Callavia? lotzei is a junior synonym of ‘P. choffati.’ The Iberian species are here assigned to C…

‘‘Distinguishing eustatic and epeirogenic controls on Lower-Middle Cambrian boundary successions in West Gondwana (Morocco and Iberia)’’, by Ed Landing, Gerd Geyer and Wolfram Heldmaier, published in Sedimentology (2006), 53(4), 899-918 - discussion

A blind trilobite with Baltic affinities from Cambrian Series 3 of the Iberian Chains, Spain, and its stratigraphical and palaeobiogeographical significance

Three cranidia of a conocoryphid trilobite are described from the lower Caesaraugustan Regional Stage (upper part of provisional Cambrian Stage 5 within Cambrian Series 3) in the Iberian Chains, Spain. The material is from the upper part of the Mansilla Formation and the base of the overlying Murero Formation. It closely resembles Bailiella tenuicincta (Linnarsson, 1879), which has previously been described from the Ptychagnostus gibbus (Cambrian Stage 5) and lower P. atavus zones (lower Drumian Stage) of Baltica (Sweden and Bornholm), and from the P. atavus Zone of West Avalonia (Newfoundland). The record of B. cf. tenuicincta from the Mediterranean margin of West Gondwana provides additio…

Presence of Naraoia Walcott, 1912 (Nektaspida, Arthropoda) in the middle Cambrian of Europe (Murero, NE Spain).

The genus Naraoia Walcott, 1912, a Burgess Shale-type fossil known from the lower and middle Cambrian of British Columbia (Canada), Idaho and Utah (USA), as well as from Yunnan and Guizhou provinces (China), is now reported from the middle Cambrian of Murero (Zaragoza, Spain), which is the first record in the Acadobaltic province. The only fragmented specimen found is determined as Naraoia sp., its age being Pardailhania multispinosa Zone (Drumian Stage). This new datum reinforces the hypothesis of the existence of a cosmopolitan faunal substrate in early Cambrian times, which is to some extent refl ected in the mid Cambrian by faunal groups of low evolutionary potential as the family Narao…

Estratigrafía y paleontología del yacimiento QUIN-18 (Formación Valmayor, Frasniense, sinclinal de Almaden, España)

n el núcleo del Sinclinal de Almadén (Ciudad Real, España) aflora una potente sucesión vulcano-sedimentaria (Complejo Vulcano-Sedimentario de Chillón), que se apoya sobre una sucesi6n esencialmente limo-pelÍtica (Fm. Yalmayor), ambas frasnienses, en el techo de esta ultima se encontr6 el yacimiento QUIN- I 8, especialmente rico en braquiópodos y ostrácodos fósiles. La edad indicada por estos correspondería a la parte alta de la Zona de Mesotaxis asymmetricus Media hasta la Zona de M. asymmetricus Superior (parte alta de la Zona de Palmatolepis punctata a la Zona de P. hassi Inferior, en la zonación estandar de conodontos).
 Los ostrácodos pertenecen al llamado ecotipo (ökotyp) eifélico…

Diagénesis, análisis de procedencia y ambiente tectónico de rocas siliciclásticas. Un caso de estudio en el Devónico Superior de la Cordillera Ibérica (Tabuenca, España)

This paper describes the petrography and infers the provenance of siliciclastic rocks from the Upper Devonian of the Iberian Chains (Tabuenca, NE Spain), and outlines the tectonic setting associated with the Ebro Massif. These Devonian deposits are constituted by four different siliciclastic units: the Rodanas, Bolloncillos, Hoya and Huechaseca Formations. The provenance and diagenesis of over 400 sedimentary rocks samples are studied with a combination of petrographic polarizing microscope, scanning electron microscopy, atomic absorption spectroscopy, X-ray fluorescence and X-ray diffraction. In this sense, AAS and XRF analysis were used to determine the content of Ca, Mg, Fe, Mn, Na, K an…

New data on Marocella (Mollusca, Helcionelloida) from the Cambrian (Series 2–Miaolingian) of the Iberian Peninsula

The present work is an overview of the current knowledge about the genus Marocella on the Iberian Peninsula, describing new specimens from the lower and middle Cambrian (Cambrian Series 2 and Miaol...

THE DEMOSPONGE GENUS LEPTOMITUS and A NEW SPECIES FROM THE MIDDLE CAMBRIAN OF SPAIN

Forty-five specimens of Leptomitus conicus sp. nov. have been collected from the base of the Murero Formation (Caesaraugustan, Middle Cambrian) in the Murero area of Zaragoza, north-east Spain. The new species is a small obconical sponge, which has coarse oxeas forming parallel rods that run the whole length of the specimens in the man- ner typical of the genus. The biostratigraphy and facies of the levels with Leptomitus conicus have been analysed. Palaeoeco- logical information derived from associated trilobites, brachio- pods and ichnofossils shows that L. conicus lived in a soft substrate of a sublittoral environment of low to low ⁄ moderate energy. According to established Cambrian pal…

Ostracod and conodont faunal changes across the Frasnian-Famennian (Devonian) boundary at Els Castells, Spanish central Pyrenees

Diverse conodont and silicified ostracod assemblages were found in the Spanish Pyrenees (Els Castells section), in the Frasnian/Famennian boundary beds (laterhenana and/orlinguiformis to latetriangularis zones), in strata below and above the well-known Kellwasser Extinction Event. Many of the ostracods studied here are conspicuous elements of the “Thuringian Mega-Assemblage”, and show maximum affinities with faunas from the southeastern Cantabrian Mountains (Spain), eastern Thuringia and the Harz (Germany). The composition of the faunas, however, is not uniform through the Els Castells section. A rather sharp break exists, roughly coinciding with the Frasnian/Famennian boundary. The break i…

Lower Ovetian (Lower Cambrian) trilobites and biostratigraphy of the Pedroche Formation (Sierra de Córdoba, southern Spain)

The low Lower Cambrian rocks from the Sierra de Cordoba, which consist of well exposed mixed facies and abundant fossil assemblages showing long stratigraphic ranges throughout the Pedroche Formation, represent one of the best successions of this age in Europe. The fossil assemblages include diverse Ovetian archaeocyaths, trilobites, small shelly fossils, calcimicrobia, trace fossils and stromatolites. Trilobites are still poorly known, and thus they are the main objective of this work. The trilobites studied originate from three sections. At the Arroyo de Pedroche 1 section, cf. Bigotinella and Bigotina bivallata are replaced towards the top by Lemdadella linaresae, Lemdadella perejoni sp.…

Biostratigraphy and palaeobiogeography of the Cambrian genusHipponicharion (Ostracoda)

The bradoriid genusHipponicharion Matthew, 1886 is one of the oldest known Cambrian ostracods. Until now, five species have been documented and another three taxa have been tentatively assigned to one or another species.Hipponicharion has been recorded from Poland, Germany, Morocco as well as from Canada and Great Britain.Hipponicharion hispanicum n. sp. represents the first Cambrian ostracod documented from Spain.Hipponicharion taidaltensis n. sp., formerlyH. aff.geyeri Hinz-Schallreuter, 1993 andH. elickii n. sp., formerlyH. cf.eos sensuElicki, 1994 have also been restudied in this paper.Hipponicharion seems to be restricted to the Acadobaltic Province sensuSdzuy (1972). The systematic re…

A Middle Cambrian edrioasteroid from the Murero biota (NE Spain) with Australian affinities

Abstract A Middle Cambrian edrioasteroid belonging to the genus Cambraster is described from the Middle Cambrian Murero biota (Cadenas Ibericas, NE Spain). Up to now, this genus was known only from Australia and France. This represents the first record of the class Edrioasteroidea in the Cambrian of Spain. Moreover, preliminary results on the diversity and biostratigraphic position of Cincta, Eocrinoidea and Edrioasteroidea from this area are reported.

The lower Ovetian Stage (lower Cambrian Stage 3) trilobite zonation in Spain and correlation with West Gondwana

New trilobites from the upper part of the Pusa Formation (base of Cambrian Stage 3) in Central Spain are studied for their systematic and biostratigraphic significance. The trilobites Proabadiella ...

New occurrence of the family Hipponicharionidae (Bradoriida, Arthropoda), in the lower and middle Cambrian of the Cadenas Ibéricas, Spain

The bradoriids Hipponicharion aff, hispanicum and Wimanicharion aff. matthewi are reported from the lower and middle Cambrian strata of the Cadenas Ibericas, Spain. The genus Hipponicharion seems to be restricted to the Acadobaltic Province. Wimanicharion has been recorded from Sweden and Canada (Nova Scotia). The new discovery of Wimanicharion in Spain indicates its similar palaeobiogeographical distribution to Hipponicharion.

The middle lower Cambrian (Ovetian)Lunagraulosn. gen. from Spain and the oldest trilobite records

AbstractThe type material ofAgraulos antiquusSdzuy, 1961 from the La Herrería Formation, northern Spain, is revised together with additional material and included in the new genusLunagraulos. The stratigraphical range ofLunagraulos antiquus(Sdzuy, 1961) – occurring below that of the trilobite species of the generaLunolenus,MetadoxidesandDolerolenusin the type locality of Los Barrios de Luna in the province of León, northern Spain – and the accompanying ichnofossil assemblage demonstrate an Ovetian age (lower part of Cambrian Stage 3, currently being discussed by the International Subcommission on Cambrian Stratigraphy) for this species. Moreover, the trilobiteLunagraulos tamamensisn. gen. n…

Cerro del Hierro, Spain: the largest exposed early Cambrian palaeokarst

AbstractWe study the largest exposed example of an early Cambrian palaeokarst, associated with laterites and developed during rifting of the Ossa–Morena Zone. The lithostratigraphy, biostratigraphy, facies and the genesis reflect episodes of sea-level fall (Cerro del Hierro Regression) related to tectonic events and palaeoclimate. This palaeokarst can be primarily considered as the result of early Cambrian polyphase karstification in an extensional tectonic regime, later modified by Neogene–Quaternary geomorphological processes. The event may correlate with other regressive events of a similar age in Spain, Italy, United Kingdom, South America and Australia. This episode also has local name…

A new Alokistocaridae Resser, 1939 (Trilobita) from the middle Cambrian of Spain

A new trilobite species, Schopfaspis? graciai, from the middle Cambrian of Spain is the first member of Alokistocaridae reported from west Gondwana. A cladistic analysis of this trilobite and other Gondwanan trilobites of possible alokistocarid affinities (Schopfaspis granulosa, Chelidonocephalus anatolicus, Derikaspis toluni, Kounamkites multiformis) suggests that this family can be divided into two subfamilies: Alokistocarinae and Altiocculinae. Schopfaspis? graciai nov. sp. and Schopfaspis granulosa are assigned to the subfamily Altiocculinae laying in a more basal position than Altiocculus species. The cladistic analysis also demonstrates a possible relationship of Chelidonocephalus ana…

Biostratigraphy of the Ribota and Huérmeda formations (Cambrian Series 2) in the Comarca del Aranda (Zaragoza province), Iberian Chains (NE Spain)

This article presents a detailed biostratigraphic analysis of the Cambrian Series 2 Ribota and Huérmeda formations of four sections of the Iberian Chains (NE Spain), and a systematic study of their trilobite faunas. We identified four major assemblages: two in the middle part of the Ribota Formation, one at the base of the Huérmeda Formation and one at the top of the Huérmeda Formation. The studied species permit the assignment of these formations to the middle and upper Marianian and probably lower Bilbilian stages in the regional stratigraphic chart for the Iberian Peninsula, which correlates with an interval around the Cambrian Stage 3–4 boundary. The assemblages exhibit a great correlat…

El género Hamatolenus Hupé, 1953 (Cámbrico Inferior-Medio) en Murero y áreas adyacentes de las CadenaS Ibéricas (NE de España)

Hasta la fecha, se han definido tres subgeneros de Hamatolenus Hupe, 1953: H . ( Hamatolenus ) Hupe, 1953, H . ( Myopsolenus ) Hupe, 1953 y H . ( Lotzeia ) Sdzuy, 1958. En Espana se conocian solo representantes de los dos primeros con las especies H . ( Hamatolenus ) ibericus Sdzuy, 1958 y H . ( L .) lotzei Sdzuy, 1958. Se presenta aqui el primer ejemplar de Hamatolenus ( Myopsolenus ) encontrado en la Peninsula Iberica. El analisis de la distribucion estratigrafica del genero Hamatolenus muestra su potencial para la correlacion de las materiales situados entorno al limite Cambrico Inferior y Medio, para las facies siliciclasticas en el ambito perigondwanico. Ademas, desde un punto de vista…