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[ES]Los cocodrilos del Eoceno y Oligoceno de la Cuenca del Duero están representados, según se desprende del estudio de los dientes aislados, por tres géneros Asiatosochus Mook (exclusivo del Nivel "Salzones", Iberosuchus Antones (no presente en el Nivel "Molino de Pico")y Diplocynodom Pomel. Los osterodermos de tres tipos muy distintos, al presentar una distribución similiar, permiten una correlación anatómica con los tres géneros. Se ha realizado un estudio estadístico de los dientes y cráneos, elaborándose diagramas triangulares, Rectas BC-RC y diagramas alveolares. En cuanto a la determinación, se prefiere Iberosuchus frente a Pristichompsum y se descarta Allognathosuchus., [EN] According to the study of isolated teeth, the crocodiles found in the Eocene and oligocene sediments of the Duero basin (Spain) belong to the three diferent Asiatosuchus Mook specifics of the sanzoles horizon, iberosuchus Antunes, not present in the "Molino del Pico" horizon, and Diplocynodon Pomel. Three diferent types of the osteoderms presenting a similar chronostratigraphical distribution to that of the teeth, allow to establish a morphological correlation between the osteoderms and the three above mentioned genera. Another crocodilia genus ocurring in the "Molino del Pico" horizon has not been yet classified.

Feathers are rare in the fossil record because they have a low fossilization potential. Despite their palaeobiological significance, they also provide important palaeoecological and taphonomic information. Here, we report a new occurrence of three isolated feathers from the shales of the Oligocene Tremembe Formation (Taubate Basin, SE Brazil). Their possible taxonomic affinities and taphonomic features are also discussed. Analyses identified the specimens as representatives of two pennaceous morphotypes (i.e., a contour and a rectrice feather). Both are preserved as carbonized traces, although, due taphonomic processes, they show different degrees of preservation. Since the Tremembe Formation is responsible for the most diverse record of Cenozoic birds, and because water-adapted birds (e.g., anseriformes and phoenicopteriformes) occur in this unit, it is highly possible that these feathers belonged to these aquatic taxa. Further investigations should concentrate on geochemical and microscopic techniques in order to reveal additional taxonomic and paleoecological features currently unknown in Paleogene birds of Brazil.

The limestones of the Fila de Cal Formation build the largest carbonate platform sequence of Costa Rica extending over 180 km from southern Costa Rica into the Panamanian boarder area of David. The detailed limestone microfacies analysis and micropaleontologic dating based on the contained larger foraminiferal assemblages of 22 samples selected from the most representative exposures reveal three main carbonate facies: (1) Eoannularia eocenicabearing spiculite facies from the Middle Eocene, (2) large lepidocyclinid-nummilitid facies from the Upper Eocene lead by the Lepidocyclina chaperi-Lepidocyclina tobleri panamensis assemblage and (3) dominant Lower Oligocene Lepidocyclina yurnagunensis-Lepidocyclina undosa assemblage. These three biostratigraphically successive facies record circa 14 to 19 m.y. of continuous shallow-marine carbonate sedimentation in the Pacific frontal arc region of southern Costa Rica. During this time large communities of benthic organisms: larger foraminifera, calcareous algae, corals, bryozoans, mollusks and equinoderms rapidly grew in warm tropical waters to build the largest and long-lasting carbonate platform on the Costa Rican arc. The carbonate sedimentation ended abruptly with accumulation of thick volcaniclastic marine platform-to-slope deposits of the Térraba Formation. Tectonically, the Fila de Cal carbonate platform development coincides with rapid convergence rates of the Farallón plate beneath southern Central America leading to strong arc uplift and new widespread neritic environments. The correlation with contemporaneous carbonate arc sequences clearly indicates that primarily their proximity to the inner volcanic arc areas and strong subsidence in response to emerging volcanic edifices are probably the main factors that controlled growing and persistence of carbonate environments within the arc setting. Resumen Las calizas de la Formación Fila de Cal constituyen la mayor secuencia de plataforma carbonatada de Costa Rica al extenderse por más de 180 km, desde el río Savegre hasta la región de David en Panamá. El análisis detallado de microfacies y micropaleontológico de las asociaciones de macroforaminíferos de 22 muestras de roca provenientes de afloramientos representativos revelan tres facies carbonatadas principales: (1) espiculitas de Eoannularia eocenica del Eoceno Medio, (2) facies de grandes lepidociclinas y nummulites del Eoceno Superior caracterizada por Lepidocyclina chaperi-Lepidocyclina tobleri panamensis y (3) facies de Lepidocyclina yurnagunensis-Lepidocyclina undosa del Oligoceno Inferior (Rupeliense). Estas tres facies, bioestratigráficamente sucesivas, documentan alrededor de 14 a 19 M.a. de continua sedimentación carbonatada nerítica en la región frontal del arco. Durante este tiempo, grandes comunidades de organismos bentónicos: macroforaminíferos, algas calcáreas, corales, briozoos, moluscos y equinodermos crecieron en aguas tropicales cálidas para formar la plataforma más extensa y duradera de Costa Rica. La sedimentación carbonatada terminó de forma abrupta con la acumulación de depósitos volcaniclásticos de plataforma y talud de la Formación Térraba. Tectónicamente, el desarrollo de la plataforma coincidió con altas tasas de convergencia de la placa Farallón por debajo de América Central, que condujo a fuerte levantamiento del arco y extensas áreas neríticas. La correlación con secuencias carbonatadas contemporáneas indican que la proximidad de las plataformas al arco interno y la fuerte subsidencia en respuesta a la emersión de nuevos edificios volcánicos son probablemente los factores que determinaron el crecimiento y persistencia de ambientes carbonatados en arcos intraoceánicos.

Duas novas espécies de ostracodes, Eucypris lobatoi sp. nov. e Potamocypris taubatensis sp. nov., são propostas neste trabalho. Este é o primeiro registro fóssil destes gêneros no Brasil, cujas espécies identificadas ocorrem em duas fases distintas do Paleolago Tremembé. Eucypris lobatoi sp. nov. ocorre durante a fase mais antiga e estável do paleolago, enquanto Potamocypris taubatensis sp. nov., na fase mais recente e instável. Estes dados corroboram uma interpretação paleolimnológica prévia baseada em ostracodes que sustenta uma tendência de raseamento do paleolago durante o final da deposição da Formação Tremembé. Two new Oligocene ostracod species, Eucypris lobatoi sp. nov. and Potamocypris taubatensis sp. nov., are herein proposed. This is the first fossil record of these genera in Brazil, and the species identified occur in two distinct phases of the Tremembé Paleolake. It is assumed that Eucypris lobatoi sp. nov. has lived in the oldest and more stable phase of the lake, Potamocypris taubatensis sp. nov., in the youngest and more unstable phase. These data support a previous ostracod-based paleolimnological interpretation which sustains a shallowing trend in the paleolake during the final deposition of the Tremembé Formation.

Purpose: Slope-associated ichnoassemblages show great variability according to the physiography of the platform-slope system, sedimentary taxa and nutrient input. Ophiomorpha rudis uses to be common in turbiditic successions, therefore its detailed characterization is essential for the understanding of this kind of deposits. Methods: Ichnological, stratigraphic and sedimentological analyses were carried out in Oligocene slope deposits in the Cala Piteres section (southeastern Spain), where exceptionally preserved Ophiomorpha rudis 3D-boxworks are present. Results: Four different sedimentary facies were recognized: (i) marls, (ii) tightly packed conglomerates, (iii) coarse-grained debrites with scattered clasts and olistoliths, (iv) gravity-flow induced calcarenites. The first facies was related to background sedimentation, while the other ones were considered to represent different gravity-flow deposits in slope channels. The ichnological analysis revealed the presence of two ichnoassemblages, dominated by Zoophycos isp. and Ophiomorpha rudis, respectively. The first ichnoassemblage developed in marls and presents Zoophycos together with Chondrites targionii and rare Rhizocorallium. The second one developed in the calcarenitic gravity-flow deposits, where Ophiomorpha exhibits complex mazes with horizontal burrows and vertical shafts. Conclusions: The horizontal development of Ophiomorpha on the upper surface of the beds would appear to follow organic matter distribution. On some bed surfaces, the cones representing the burrows entrance are preserved, this allowing for the estimation of the burrows penetration depth and for a detailed characterization of the colonization surface and of the whole burrow architecture. The study of the previously described ichnoassemblages let us consider the studied section as an expression of the Ophiomorpha rudis ichnosubfacies in an upper slope. Objetivos: Topografía, nutrientes y tasa de sedimentación son los parámetros que suelen determinar la variabilidad de las icnoasociaciones de plataforma-talud. La ubicuidad de Ophiomorpha rudis en entornos turbidíticos hace que su caracterización sea indispensable en la comprensión de dicha variabilidad. Métodos: Se realiza un estudio icnológico, estratigráfico y sedimentológico de detalle de la sección de Cala Piteres (Alicante, SE España), donde afloran ejemplos excepcionales de complejos de galerías de Ophiomorpha rudis. Resultados: Diferenciamos 4 facies sedimentarias, una de ellas (margas), corresponde a la sedimentación autóctona del talud, mientras que las tres restantes (brechas clasto-soportadas, debritas con olistolitos y calcarenitas) representan diferentes tipos de flujos gravitacionales. En este entorno, el análisis icnológico ha evidenciado la presencia de dos icnoasociaciones, la primera, desarrollada en los niveles margosos, dominada por Zoophycos reelaborados localmente por Chondrites targionii, y una segunda, típica de los niveles de calcarenitas turbidíticas, caracterizada por complejos retículos 3D de Ophiomorpha rudis. Conclusiones: Los conos de sedimento bioturbado que aparecen en el techo de varias turbiditas son reconocidos como la superficie original de colonización de la red de galerías de O. rudis. Esta circunstancia permite concluir que la distribución de materia orgánica, especialmente abundante a techo de la turbidita, es el mayor condicionante del desarrollo horizontal de las galerías. Además, permite una estimación más ajustada de la profundidad de las pistas y una reconstrucción detallada de su arquitectura. Por último, la alternancia de icnoasociaciones (Zoophycos/Ophiomorpha rudis), permite identificar la ichnosubfacies de O. rudis en la zona superior del talud, de transición a la icnofacies de Zoophycos. This research was supported by the project CGL2015-66835-P, financed by the Spanish Ministry of Education and Science (MINECO, Government of Spain).

The present paper deals with the description of the first remains of the Family Mesotheriidae in the Quebrada Fiera locality. The fauna from Quebrada Fiera comes from sediments nowadays considered to represent the base of the Agua de la Piedra Formation. The recovered faunal assemblage includes typical elements of the Deseadan Age (late Oligocene), shared with both Patagonian and lower latitude associations (e.g., Salla, Bolivia). A unique specimen of Mesotheriidae has been recovered after several field seasons since 2006. It is a palatal portion in two fragments, one bearing the I1 and the other with left P4-M2 and right M1-2. Morfological and metrical features of this material reveal a taxon much closer to the Patagonian mesotheriid species Trachytherus spegazzinianus than to the Bolivian taxa, T. alloxus and T. subandinus, and it is determined as Trachytherus cf. T. spegazzinianus. Its presence in Mendoza fills a gap in the expected geographical distribution of this mesotheriid, as it was also recorded in the Bolivian site of Lacayani. The scanty record of mesotheriids in Quebrada Fiera contrasts with Salla and Patagonian localities. Fil: Cerdeño Serrano, Maria Esperanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentina

Los registros paleógenos de Cingulata Glyptodontidae son muy escasos y los mejores conocidos provienen de la actual región patagónica de Argentina. Dos subfamilias han sido descritas: Glyptatelinae y Propalaehoplophorinae. Los registros paleógenos de Propalaehoplophorinae provienen de la localidad El Pajarito (Oligoceno Tardío, SALMA Deseadense), provincia de Chubut, Argentina. Aquí damos a conocer el registro más septentrional de un Propalaehoplophorinae, proveniente de la Formación Fray Bentos (Oligoceno Tardío, SALMA Deseadense) de la localidad Cueva del Tigre, Chajarí, provincia de Entre Ríos, Argentina. Desde una perspectiva morfológica, estos restos son casi idénticos con aquellos reportados para El Pajarito. Esto demuestra que durante el Paleógeno la distribución latitudinal de los Propalaehoplophorinae fue mucho mayor a la previamente conocida., Paleogene records of Cingulata Glyptodontidae are scarce. The only well described comes from the Paleogene of Argentine Patagonia. Two subfamilies have been reported for that period: Glyptatelinae and Propalaehoplophorinae. Until this contribution, the latter taxon was geographically restricted to the locality of El Pajarito (Late Oligocene, Deseadan SALMA), Chubut province, Argentina. Here we present and describe the northernmost record of a Paleogene Propalaehoplophorinae. The material is represented by three associated osteoderms of the dorsal carapace from the Fray Bentos Formation (Late Oligocene, Deseadan SALMA) in the locality of Cueva del Tigre, Chajarí, Entre Ríos province, Argentina. Morphologically, these remains are almost identical to those reported from the late Oligocene of the Patagonian region, showing that during the Paleogene the Propalaehoplophorinae had a larger latitudinal distribution than previously known., Facultad de Ciencias Naturales y Museo

Nannofossil data from ODP Site 711 (equatorial Indian Ocean) yield a set of consistent, reliable biohorizons that form the basis of a revised calcareous nannofossil biostratigraphy for the low-latitude Eocene-Oligocene. We discuss 31 biohorizons occurring over an 11 myr time interval which we correlate to previous magnetostratigraphic data. Calcareous nannofossils from the middle Eocene through the lower Oligocene of the studied section are characterized by moderately well preserved assemblages consisting largely of low latitude and cosmopolitan species. A significant nannofossil dissolution interval is evidenced at the middle Eocene Climatic Optimum (MECO). We document a significant increase in late Eocene nannoplankton exhibiting a eutrophic preference. Analysis of the assemblage suggests important changes in the equatorial oceanic regime just before the onset of the Eocene-Oligocene transition (EOT), that foreshadow the more dramatic climatic shift of the early Oligocene.

Middle Cenozolc marine fossil-bearing beds crop out in the Cerro Plataforma (western Chubut Province. Argentina) at about 1,400 m a.s.l. They are located 500 km far from the modern Atlantic coast and only 50 km from the Pacific Ocean. Well preserved penguin bones and a shark tooth were found therein. Invertebrates include corals, bryozoans, abundant mollusks, echinoids, and crabs. Morphogeometric analysis and comparative description confirmed that the penguin humerus is referable to Palaeospheniscus bergi Moreno and Mercerat, 1891. Most of the fossils indicate a Miocene age. However, there is a debate about if the bearing beds are of Pacific or Atlantic origin. Fossil invertebrates identifiable at species level reveal Pacific affinity, the shark species is cosmopolitan, and Palaeospheniscus bergi is known from early Miocene Atlantic units of southern South America. Yet, Palaeospheniscus Moreno and Mercerat, 1891 is also known from Miocene Pacific beds but it has not been identified at specific level yet. This is the highest site in topographic terms in which penguin fossils occur. This indicates a remarkable uplift for the area, probably from the middle Miocene. Capas portadoras de fósiles marinos del Cenozoico medio afloran en cerro Plataforma (oeste de la Provincia del Chubut, Argentina) a unos 1.400 m s.n.m. Están localizadas a 500 km de la costa pacífica actual y a solo 50 km de la pacífica. Fueron hallados restos de pingüinos y un diente de tiburón bien preservados. Entre los fósiles de invertebrados se incluyen corales, briozoos, abundantes moluscos, equinoideos y cangrejos. Los análisis morfogeométricos y la descripción comparada confirmaron la asignación del húmero de pingüino a Palaeospheniscus bergi Moreno y Mercerat, 1891. La mayoría de los fósiles indican una edad Miocena. Sin embargo, existe un debate sobre si estas capas poseen un origen pacífico o atlántico. Los fósiles de invertebrados identificables a nivel de especie presentan afinidades pacíficas, la especie de tiburón es cosmopolita, y Palaeospheniscus bergi es conocido en unidades atlánticas del Mioceno temprano de América del Sur. A pesar de esto, el género Palaeospheniscus Moreno y Mercerat, 1891 es también conocido en capas miocenas del Pacífico, aunque la especie no ha sido aún identificada. En términos topográficos, este es el sitio más elevado en el que se han hallado restos de pingüinos. Esto indica un notable levantamiento del área, probablemente durante el Mioceno medio.

Depósitos clásticos de la Formación Rancahué (Oligoceno Superior), que constituye parte del registro volcánico y sedimentario de la cuenca oligocena-neógena de Aluminé (Cordillera de los Andes, 70ºW y 39ºS), permitieron analizar los fenómenos de interacción sedimentaria en ambientes volcánicos continentales y caracterizar los mecanismos de preservación de restos de troncos asociados a sucesiones aluviales volcano-sedimentarias. En estos depósitos, se ha identificado un bosque petrificado de tierras altas con 33 ejemplares preservados en posición de vida, con Nothofagoxylon como elemento dominante, desarrollado bajo condiciones climáticas templadas y húmedas. En el área de estudio, la Formación Rancahué se caracteriza por la estrecha interrelación lateral y secuencial entre tres asociaciones de facies. La asociación A se compone de aglomerados y conglomerados gruesos monomícticos (con fenoclastos de basaltos) acumulados en ambientes proximales de altas pendientes (taludes y en el pie de taludes subaéreos) como producto de ʻdebris floodsʼ o de flujos hiperconcentrados, avalanchas, deslizamientos y flujos de detritos. Estos depósitos tienen procedencia local y se vinculan con un cuerpo volcánico basáltico que generó un importante relieve intracuencal. La asociación B consiste en conglomerados, sabulitas, areniscas conglomerádicas y areniscas gruesas y muy gruesas con variadas estructuras primarias y se asigna a un sistema fluvial con desarrollo regional, baja canalización y carga traccional, con áreas de aporte en la cordillera de los Andes. La asociación C se compone de facies clásticas de textura fina, acumuladas esencialmente por decantación en ambientes subaéreos y subácueos, con el periódico aporte de lluvias de cenizas volcánicas, y con niveles en los que se aprecia la formación de suelos. Los depósitos fluviales incluyen restos de troncos transportados que muestran el poder erosivo de las corrientes de flujo rápido que los acumularon. El bosque petrificado arraigó en depósitos de la asociación de facies C y quedó preservado en los suprayacentes aglomerados y conglomerados de la asociación A. Se interpreta que los troncos fueron sepultados por los flujos gravitacionales que operaron en abanicos aluviales y coluviales de la zona riparia hidrogeomórfica y que se caracterizan por una tasa de sedimentación alta y un discreto poder erosivo por su naturaleza laminar o quasi laminar., The siliciclastic deposits of the Rancahué Formation (Oligocene, Aluminé Basin), formed in the eastern side of the Andean Cordillera (70°W y 39°S) are studied to evaluate the relationship among different depositional systems in volcanic settings and to disclose the processes that contributed to the preservation of a forest developed at the foot of a volcanic relief. In the alluvial volcano-sedimentary record of the Rancahué Formation an upland petrified forest with 33 logs in life position was identified. This flora, with Nothofagoxylon as the main taxon, was developed under temperate and humid climatic conditions. Three facies associations were defined in the study region. Facies association A was accumulated in subaerial talus and foot-talus slopes, and is composed of monomictic (basaltic) boulder and cobble conglomerates formed by debris floods, hyperconcentrated flows, avalanches, landslides and debris flows. The source of these sediments is local and is related to the growth of an intrabasinal basaltic volcanic edifice. Facies association B consists of cross-stratified, plane bedded and massive conglomerates, pebbly sandstones and coarse-grained sandstones accumulated in a regional braided fluvial system with source areas located in the Andean Cordillera. Facies association C is characterised by fine-grained sediments accumulated in subaerial and subaqueous environments, with periodic contribution of ash falls and development of palaeosols. The forest rooted in deposits of facies association C, and the logs preserved in life position are located within the overlying coarse-grained volcaniclastic deposits of facies association A. The burial and preservation of this vegetation was favoured by the highly aggrading rhythm and comparative low erosive power of the gravitational flows that operated in alluvial and colluvial fans of the riparian hydrogeomorphic zone. Conversely, abundant transported and broken trunks included in the deposits of facies association B clearly indicate the strong erosive power of the currents of the associated braided fluvial system., Centro de Investigaciones Geológicas

La Cuenca de Aluminé constituye un área de acumulación volcano-sedimentaria localizada en el retroarco andino a los 39°S. Forma parte de un conjunto de depocentros denominado Cuenca de Bío Bío-Aluminé, integrando su parte más austral. Estudios estratigráficos, geocronológicos, sedimentológicos y estructurales realizados sobre el relleno de la cuenca indican que la misma habría evolucionado en dos etapas: una etapa extensional oligocena, integrada por lavas basálticas y sedimentos producidos por el retrabajo del material volcanoclástico asociado a depósitos piroclásticos (Formación Rancahue) y otra etapa contraccional del Mioceno Tardío, con depósitos aluviales y piroclásticos coronados por efusiones basálticas (formaciones Chimehuín y Tipilihuque). El relleno de la etapa extensional es fuertemente volcánico y tiene proveniencia del oeste, vinculado al profuso volcanismo basáltico oligoceno del área andina chilena. La etapa contraccional adopta la forma de una cuenca intramontana, localizada entre las cadenas levantadas principalmente por la inversión de estructuras extensionales mesozoicas y muestra fuerte asimetría y proveniencia desde el este. Evidencias estructurales y geomorfológicas indican la existencia de un hiatus depositacional entre ambas etapas. The Aluminé Basin is a volcano-sedimentary depocentre located in the Andean retroarc at 39°S. It is the southern part of a major depositional system: the Bío Bío-Aluminé Basin. Stratigraphical, geochronological, sedimentological and structural analysis allow us to conclude that the basin evolved through two stages: an Oligocene extensional stage filled with basalts and reworked volcaniclastic and pyroclastic deposits (Rancahue Formation) and a Miocene contractional stage, filled with alluvial and pyroclastic deposits covered by basaltic lavas (Chimehuín and Tipilihuque formations). The volcanic-rich (basaltic) infill of the extensional stage has a western provenance and was derived from widespread magmatic activity that took place during the Oligocene in the adjacent cordilleran axis. The contractional stage basin is an intramontane depocentre limited by uplifted blocks generated mainly by the inversion of Mesozoic extensional faults. It is strongly asymmetric and shows eastern provenance. Structural and geomorphological evidence indicate the existence of a non-depositional hiatus between the two stages. Centro de Investigaciones Geológicas

The Late Oligocene first occurrence of Miogypsina gunteri Cole and Miogypsina tani Drooger is verified in the light of larger foraminiferal assemblages from Nosara (Nicoya Peninsula, Costa Rica) and Windward (Carriacou, Grenada, Lesser Antilles). At Windward, they co-occur with planktonic foraminifera and nannofossils studied by earlier workers. 87Sr/86Sr isotope ratios were measured in calcite of larger foraminifera at both sites to determine independent absolute ages of the two outcrops. Late Oligocene shallow water formations unconformably overlie Paleocene-Eocene distal turbidites and siliceous shales in the outcrops in Costa Rica. The shallow-water lithostratigraphy includes near shore volcanic sandstones that alternate with sandy bioclastic limestones. The latter have yielded rich assemblages of larger foraminifera that have been studied in oriented sections, SEM for split material and polished rock thin sections for transmitted light and cathodoluminescence (CL) observation. The association of larger foraminifera includes Heterostegina antillea Cushman, Miogypsina tani Drooger, Miogypsina gunteri Cole, Miogypsina c.f (Miolepidocyclina) panamensis (Cushman), Miogypsina sp., Lepidocyclina (nephrolepidina) vaughani Cushman, Lepidocyclina yurnagurensis Cushman, Lepidocyclina undosa Cushman. At Windward, scattered outcrops of the Belvedere Formation expose mass flow deposits rich in larger foraminifera associated with an early late Oligocene (NP24) planktonic foraminifa assemblage. Planktonic foraminifera and nannofossils recovered in rocks slightly downsection indicate an upper Middle Oligocene age. Larger foraminifera species collected just north of Windward include Lepidocyclina undosa Cushman and Miogypsina gunteri Cole. The 87Sr/86Sr ratio was measured in 11 specimens of megalosphaeric Lepidocyclina spp., mechanically extracted from 2 rock samples collected at Punta Peladas (Costa Rica) Ratios range from 0.709088 to 0.708196, which correspond to a model age of 27.4 to 24.94 Ma. Very similar ratios, ranging from 0.708150 to 0.708167 were obtained from Windward Village (Carriacou). All measured 87Sr/86Sr ratios fall within a Chattian (Late Oligocene) age. Nannofossils, planktonic foraminifera and identical 87Sr/86Sr ratios from Punta Peladas and Windward clearly indicate a Chattian (Upper Oligocene) first occurrence of Miogypsina gunteri and Miogypsina tani and confirm this age range for the other larger foraminifera cited above. The first occurrence of Miogypsina gunteri in the lower Aquitanian and Miogypsina tani in the upper Aquitanian as proposed by European workers cannot be confirmed. .