STUDIES ON PYCNODONT FISHES (II): REVISION OF THE SUBFAMILY PYCNODONTINAE, WITH SPECIAL REFERENCE TO ITALIAN FORMS

The diagnosis, composition, and phylogenetic relationships of the European subfamily Pycnodontinae are revised; its record is pushed back from the Cenozoic into the Mesozoic. The Pycnodontinae is confirmed as a monophyletic group. It is diagnosed by: thin, laminar supraoccipital exposed all along the posterior border of the skull roof; cleithrum with two posterior expansions framing the notch for the pectoral fin; reduction in the ossification of the flank scales (clathrate pattern); reduction of the preopercular into a very low bone, never higher than the exposed, ornamented portion of the dermohyomandibular; and presence of a bifid cloacal scale. The subfamily includes the tribe Pycnodontini (Pycnodus + Oropycnodus), Polazzodus, Sylvienodus, and Tergestinia. The former “Coelodus” gridellii is moved to Polazzodus gridellii n. comb. The Italian genera,  Pycnodus, Polazzodus, and Tergestinia, form a monophyletic group together with the French Oropycnodus. The present analysis shows that Polazzodus, Sylvienodus, and Tergestinia are pycnodontin fishes, but. Haqelpycnodus, Libanopycnodus, Scalacurvichthys, and Sigmapycnodus do not belong to the Pycnodontinae. “Pseudopycnodus” and “P. nardoensis” are considered nomina dubia. This revision has revealed new aspects of the last known diversification in the evolutionary history of the Pycnodontiformes, showing that the group was still thriving in the Western Tethys during the Late Cretaceous. For the present analysis, additional arguments involving ontogenetic restrictions are provided to favour ordering multistate characters in pycnodonts

A new genus and species for the amiiform fishes previously assigned to Amiopsis from the Early Cretaceous of Las Hoyas, Cuenca, Spain

The Mesozoic actinopterygian fish Amiopsis has been reported from three different localities in the Iberian Peninsula. Amiopsis woodwardi was described from the Berriasian–Valanginian of El Montsec (Lérida, Spain). Isolated vertebral centra referred to Amiopsis were found in the Barremian of Buenache de la Sierra (Cuenca, Spain). Finally, amiiform material from the Barremian of Las Hoyas (Cuenca, Spain) were reported as Amiopsis cf. A. woodwardi, due to the overall similarity with the species from El Montsec. Here a detailed anatomical description of the material from Las Hoyas is provided for the first time. The unique combination of characters seen in this taxon, some of which are not shared with Amiopsis but with more derived amiids, indicates that it represents a new taxon, which is here named Hispanamia newbreyi gen. nov., sp. nov

History of two lineages: Comparative analysis of the fossil record in Amiiformes and Pycnodontiformes (Osteischtyes, Actinopterygii)

Amiiformes and pycnodontiformes are two orders of neopterygian fishes that were broadly distributed, and frequently appeared together, during the Mesozoic. Comparison of their fossil record reveals both common traits and significant differences. They both appeared in the Western Tethys and reached maximum diversity during the Cretaceous. The differences in their evolutionary history involve dissimilar patterns of diversity and disparity; pycnodonts are more diversified taxonomically and present larger ecomorphological disparity. This implies that they used different strategies to compete with teleosts, which were unable to displace them from their specialized niches for more than 100 ka. The reasons why this did not happen sooner are difficult to approach, and may include radical environmental changes (i.e., marine transgressions, opening of the Atlantic, closing of the Tethys and opening of the Mediterranean). It is nonetheless clear that the evolutionary novelties of the Teleostei per se were not enough to grant them advantage in the competition for the ichthyofagous and durophagous niches at least during the Late Triassic, the whole Jurassic and the Early Cretaceou

Phylogenetic relationships of Chanidae (Teleostei: Gonorynchiformes) as impacted by Dastilbe moraesi, from the Sanfranciscana basin, Early Cretaceous of Brazil

Fossil gonorynchiform fishes range from the Lower Cretaceous to the early Miocene, and are represented by a few dozen living species. The order is currently divided into two major clades: Gonorynchoidei, which includes the families Gonorynchidae and Kneriidae, and Chanoidei, encompassing a single family, Chanidae, with a single recent species, the Indo-Pacific Chanos chanos, and several fossil taxa. Chanidae includes some poorly known taxa, such as Dastilbe moraesi, described from the Aptian (Lower Cretaceous) of the Areado Formation, Sanfranciscana basin, Brazil. This species is currently considered to be a junior synonym of the type species of its genus, Dastilbe crandalli, from Santana Formation, Aptian, northeastern Brazil. The analysis of abundant D. moraesi specimens revealed several new morphological features, many of which had previously been misinterpreted. Dastilbe moraesi was incorporated into a gonorynchiform character matrix as revised and modified for the Chanidae. We obtained a single most parsimonious tree in which D. moraesi is distinct and phylogenetically apart from D. crandalli. According our analysis, D. moraesi forms a sister pair with Chanos, a clade which is closely related to Tharrhias, all composing the tribe ChaniniGonorynchiformes fósseis ocorrem desde do Cretáceo inferior ao Mioceno inferior, e são representados por alguns representantes viventes. A ordem está dividida atualmente em dois clados principais: Gonorynchoidei, que inclui as famílias Gonorynchidae e Kneriidae, e Chanoidei, compreendendo uma única família, Chanidae, com uma única espécie vivente, Chanos chanos, do Indo-Pacífico, além de vários representantes fósseis. Chanidae inclui alguns táxons problemáticos, tais como Dastilbe moraesi, descrito do Aptiano (Cretáceo Inferior) da Formação Areado, bacia Sanfranciscana, Brasil. Esta espécie é atualmente considerada um sinônimo júnior da espécie-tipo de seu gênero, Dastilbe crandalli, da Formação Santana, Aptiano do nordeste do Brasil. A análise de abundante material de D. moraesi revelou várias novas características anatômicas, muitas das quais haviam sido previamente mal interpretadas. Dastilbe moraesi foi incorporado em uma matriz revisada de caracteres da família Chanidae. Nós obtivemos uma única árvore mais parcimoniosa na qual D. moraesi é distinto e filogeneticamente distante de D. crandalli. De acordo com nossa análise, D. moraesi é o grupo-irmão de Chanos, um clado intimamente relacionado a Tharrhias, com todos compondo a tribo ChaniniThis study was supported by CNPq (process # 401818/2010-1) and project CGL2013-42643P, Ministerio de Ciencia e Innovación de Españ

Taphonomy

Trabajo presentado en el II International Symposium on Lithographic Limestones celebrado en Cuenca.-- Field trip guide book.The taphonomic anal ysis of the Las Hoyas site is still at an early stage. This analysis is necessary since it is considered a prerequisite for paleoecological reconstructions (Shipman, 1981). Besides, taphonomic analysis has its own aims; in this case they could be summarized as the establishment of the temporal succession of processes which led to the formation of the site.Peer reviewe

The Exceptional Fossil Site of Las Hoyas (SPAIN) from an Educational Perspective

The paleontological heritage of the fossil site of Las Hoyas (Early Cretaceous of Cuenca, Spain) is becoming a relevant part of the sociocultural identity of Castilla-La Mancha autonomous community in general, and of Cuenca province in particular. The most recent scientific advances, including several fossil findings that have had high scientific impact, have made Las Hoyas to regularly be the center of attention in the local, national, and international media, especially since the reinterpretation of the paleoecosystem represented by the locality published in 2010. These results have led to a renaissance of the interest of the society for this unique site. As a consequence, Las Hoyas has been declared Site of Cultural Interest by the regional government, in the form of paleontological zone. This recognition, which grants the locality with the highest level of protection, sets a legal framework for the educative initiatives developed at this locality, which can be categorized as non-formal education, formal education, and Social Paleontology.Unidad de Paleontología, Departamento de Biología, Universidad Autónoma de Madrid, EspañaJURASSICA Museum, SuizaDepartment of Geosciences, University of Fribourg, SuizaMuseo Geominero, Instituto Geológico y Minero de España, EspañaDepartamento de Estratigrafía, Universidad Complutense de Madrid, EspañaGéosciences Rennes Unité Mixte de Recherche, Centre National de la Recherche Scientifique, FranciaDepartamento de Ecología, Universidad Autónoma de Madrid, EspañaLaboratoire de Géologie de Lyon: Terre, Planètes, Environnement, Unité Mixte de Recherche, Centre National de la Recherche Scientifique, Franci

Late cretaceous continental and marine vertebrate assemblages of the Laño Quarry (Basque-Cantabrian Region, Iberian Peninsula): An update

The vertebrate-bearing beds of the Laño quarry (Condado de Treviño) are among the most relevant sites from the Late Cretaceous of Europe. Geologically, Laño and the adjacent region are set on the southern limb of the South-Cantabrian Synclinorium (SE Basque-Cantabrian Region, northern Iberian Peninsula). The Laño sites were discovered in 1984; thousands of bones and teeth, including microfossils, have been collected during the prospection in the field and excavation campaigns. The vertebrate remains occur at two different stratigraphic horizons within a continental to shallow marine succession of Late Campanian-Maastrichtian age. The lower horizon contains the Laño 1 and Laño 2 sites, whereas the upper horizon contains the Albaina site. In the Laño sites, three fossiliferous beds (called L1A, L1B and L2) are known within an alluvial system composed mainly of fluvial sands and silts. The sedimentary structures are consistent with channel areas within an extensive braided river system. Based mainly on stratigraphic correlations, the fluvial beds of Laño are regarded as Late Campanian to Early Maastrichtian in age. These deposits have yielded a very diverse vertebrate assemblage, which consists of nearly 40 species, including actinopterygians, lissamphibians, lepidosaurs, turtles, crocodyliforms, dinosaurs, pterosaurs, and mammals. Seven genera and ten species have been erected to date in Laño. With reference to the marine vertebrate association of Albaina, it consists of at least 37 species, including sharks and rays, actinopterygians, mosasaurids, and plesiosaurs. Two genera and species of rhinobatoids (family indet.) and two new species of rhinobatids have been erected in Albaina. The fossil association indicates a Late (but not latest) Maastrichtian age. Recently, isolated turtle and dinosaur fossils have been discovered in the sublittoral beds of Albaina. The Laño quarry is one of the most noteworthy Campanian-Maastrichtian vertebrate localities of Europe by its taxonomic diversity, and provides useful information about the composition and affinities of both continental and marine vertebrate faunas from the latest Cretaceous of southwestern EuropeLos niveles con fósiles de vertebrados de la cantera de Laño (Condado de Treviño) se cuentan entre los más importantes del Cretácico Superior de Europa. Desde un punto de vista geológico, Laño y la región adyacente forman parte del flanco sur del Sinclinorio Subcantábrico (SE de la Región Vasco-Cantábrica). El descubrimiento de los niveles fosilíferos remonta a 1984; las prospecciones de campo y las campañas de excavación han proporcionado miles de huesos y dientes, incluyendo microfósiles. Los restos de vertebrados aparecen en dos horizontes estratigráficos diferentes formando parte de una sucesión continental a marina litoral de edad Campaniense superior a Maastrichtiense. El horizonte inferior contiene los yacimientos de Laño 1 y Laño 2, mientras que el superior contiene solo uno: Albaina. En los yacimientos de Laño, se reconocen tres niveles fosilíferos (llamados L1A, L1B y L2) formados en el seno de un sistema aluvial compuesto por arenas y limos fluviales. Las estructuras sedimentarias indican áreas de canal dentro de un sistema trenzado muy extendido. Según las correlaciones estratigráficas, los depósitos fluviales de Laño son de edad Campaniense superior a Maastrichtiense inferior. Estos depósitos han proporcionado una asociación muy diversa de vertebrados, que consiste en cerca de 40 especies, incluyendo actinopterigios, lisanfibios, lepidosaurios, tortugas, cocodrilos, dinosaurios, pterosaurios y mamíferos. En Laño se han definido hasta el momento siete géneros y diez especies. Por lo que respecta a la asociación de vertebrados marinos de Albaina, se han reconocido al menos 37 especies, que incluyen tiburones y rayas, actinopterigios, mosasaurios y plesiosaurios. Hasta la fecha se han definido en Albaina cuatro nuevos rinobatoideos: dos especies de rinobátidos y dos géneros y especies cuya familia es indeterminada. La asociación fósil es de edad Maastrichtiense superior no terminal. Recientemente se ha descrito el hallazgo de restos fósiles aislados de tortugas y dinosaurios en los niveles marinos de Albaina. La cantera de Laño es una de las localidades de vertebrados más destacadas del Campaniense-Maastrichtiense por su diversidad taxonómica, y proporciona información relevante sobre la composición y afinidades de las faunas de vertebrados continentales y marinos del Cretácico final del suroeste de EuropaField research in the Laño quarry has been supported by financial aids of the Ministerio de Economía y Competitividad (MINECO projects CGL2010-18851/BTE and CGL2013-47521-P), Ministerio de Ciencia e Innovación (CGL2007-64061/BTE), Ministerio de Ciencia y Tecnología (CGL2004-02338/BTE, BTE2001-0185-C02-01, BOS2000-1369), Ministerio de Educación y Ciencia (Acción Integrada hispano-francesa 201-B), Diputación Foral de Álava/Arabako Foru Aldundia (93/23, 95/A23), Gobierno Vasco/Eusko Jaurlaritza (IT834-13, IT-320-10, IT-361-07, GV121.310-4/87), Universidad del País Vasco/Euskal Herriko Unibertsitatea (9/ UPV00121.310-15303/2003), Centre National de la Recherche Scientifique (CNRS, France), Institut National des Sciences de l’Univers (INSU), The Dinosaur Society (research grant 1997) and the National Geographic Research (grant #6597-99). This work is part of a palaeontological collaboration (Convenio específico de colaboración) between the Universidad del País Vasco/EHU, the Centre National de la Recherche Scientifique (CNRS, France) and the Muséum National d’Histoire Naturelle (MNHN, Paris). Contribution ISEM n° 2015-04

Teleosteos primitivos del Cretacico inferior español|bórdenes elopiformes y gonorynchiformes

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento Biología. Fecha de lectura: 29-05-199

STUDIES ON PYCNODONT FISHES (I): EVALUATION OF THEIR PHYLOGENETIC POSITION AMONG ACTINOPTERYGIANS

One of the main pending, unsolved problems concerning the study of the pycnodont fishes is their phylogenetic relationships with other major actinopterygian groups. The Pycnodontiformes have often been proposed as the sister group of the Telostei or the Teleosteomorpha. The first extensive cladistic analysis on pycnodont relationships is hereby attempted by coding Pycnodontiformes into a previously existing data matrix with major neopterygian groups: Lepisosteiformes, Semionotiformes, Macrosemiiformes, Halecomorphi, and Teleostei. This analysis has resulted on the Pycnodontiformes having an unexpected position as the most basal Neopterygii among the groups included. Therefore, pycnodonts are not the sister-group of teleosteans, and they are not holosteans either. The phylogenetic relationships and the definition of the Holostei and the Gynglimodi are not affected by the inclusion of the Pycnodontiformes, but the basal position of the latter among Neopterygii may affect the definition of this traditional major actinopterygian group. A collateral consequence of these results is that the Halecostomi can be re-defined as the clade formed by [Holostei + Teleostei]. The phylogenetic relationships of pycnodonts should, consequently, be solved among basal neopterygian groups, mostly from the Triassic, as well as relevant non-neopterygian actinopterygians in order to confirm the neopterygian affinities of the Pycnodontiformes and to verify the definition and diagnosis of the Neopterygii and the Halecostomi