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Bryozoans with calcified frontal shields formed by the fusion of costae, collectively constituting a spinocyst, are traditionally assigned to the family Cribrilinidae. Today, this family is regarded as nonmonophyletic. In the Argentine Cenozoic, cribrilinids were until recently represented by only two fossil species from the Paleocene of Patagonia. This study describes the first fossil representatives ofJolietinaandParafigularia:J. victorian. sp. andP. pigafettain. sp., respectively. A fossil species ofFigularia,F. elcanoin. sp., is also described. The material comes from the early Miocene of the Monte León and Chenque formations (Patagonia, Argentina). For comparison, we also provide redescriptions of the remaining extant species ofJolietina:J. latimarginata(Busk, 1884) andJ. pulchraCanu and Bassler, 1928a. The systematic position of some species previously assigned toFigulariais here discussed.Costafigularian. gen. is erected, withFigularia pulcherrimaTilbrook, Hayward, and Gordon, 2001 as type species. Two species previously assigned toFigulariaare here transferred toCostafigularia, resulting inC. jucundan. comb. andC. tahitiensisn. comb. One species ofFigulariais reassigned toVitrimurella, resulting inV. amplan. comb. The family Vitrimurellidae is here reassigned to the superfamily Cribrilinoidea. The subgenusJuxtacribrilinais elevated to genus rank.Inferusiais regarded as a subjective synonym ofParafigularia.Parafigularia darwiniMoyano, 2011 is synonymized withI. tayloriKuklinski and Barnes, 2009, resulting inParafigularia taylorin. comb. Morphological data suggest that these genera comprise different lineages, and a discussion on the disparities among cribrilinid (sensu lato) spinocysts is provided.UUID:http://zoobank.org/215957d3-064b-47e2-9090-d0309f6c9cd8

The cheilostome bryozoan genus Taylorius Gordon, 2014 comprises six named living and fossil species from New Zealand and one Recent species from South Africa. Taylorus nom. nov. is proposed as a re...

Geological studies in the northern sector of the Chaco foreland Basin, Bolivia, yielded new fossils coming from late Oligocene-late Miocene of the Petaca Formation. Few fossil mammals were known from the Subandean Region of Bolivia. We report a partially complete mandible of a hegetotheriid Hegetotheriinae (Notoungulata, Typotheria) from Abapo (Rio Grande River). The specimen (YPFB-LIT-PAL-005) is very close in size and dental morphology to the late Oligocene (Deseadan South American Land Mammal Age, SALMA) — Santacrucian (early Miocene) Prohegetotherium schiaffinoi (Kraglievich 1932) from Fray Bentos (Uruguay and Argentina), Salla (Bolivia), Divisadero Largo-Potrerillos and Quebrada Fiera (Argentina). However, mandibular characteristics, as the shape with a marked change in height along its length, increasing towards the back, a prominent masseteric crest, a deep mandibular groove, and a remarkable thickening of the ventral rim of the mandible, indicate differences between this specimen and Prohegetotherium schiaffinoi and the other Hegetotheriinae. The affinity of YPFB-LIT-PAL-005 with P. schiaffinoi suggests a late Oligocene to early Miocene for the upper bearing horizon of the Petaca Formation (in Abapo), an older age than previously assigned to the top of this unit (late Miocene), and confirms the taxon distribution between ∼ 36 ° to ∼ 17 ° south latitude., Facultad de Ciencias Naturales y Museo, Centro de Investigaciones Geológicas

La familia Chaperiidae alcanza su máxima biodiversidad en el hemisferio sur. El principal rasgo morfológico que caracteriza a la familia es un par de láminas calcáreas asociadas con la inserción de los músculos oclusores del opérculo. El propósito de este trabajo es describir a Aluis spinettai gen. et sp. nov., a partir de material obtenido en las Formaciones Monte León, Chenque y Puesto del Museo (Mioceno temprano, Patagonia, Argentina). A. spinettai posee colonias erectas bilaminares, suturas crenuladas entre los zooides, un extenso criptocisto y ovicelas esféricas, y carece de gimnocisto, espinas orales y avicularias. La nueva especie exhibe una notable convergencia morfológica con una especie del género Aspidostoma del Mioceno temprano (Fm. Chenque) en Patagonia. En algunas zonas de la colonia los zooides presentaban perforaciones circulares en el criptocisto realizadas por un depredador desconocido. A. spinettai presenta una distribución estratigráfica que va desde ~19 a 17 Ma (Burdigaliano). Su presencia sugiere una correlación entre los niveles superiores de la Formación Monte León y los inferiores de la Formación Chenque. La distribución paleogeográfica de esta nueva especie abarca al menos 500 km a lo largo de la costa atlántica austral de Sudamérica. Los representantes actuales de la familia Chaperiidae en el Atlántico Sudoccidental no parecen relacionados con A. spinetta. The family Chaperiidae reaches its highest biodiversity in the southern hemisphere. The main morphological feature characterizing the family is a pair of calcareous laminar structures associated with the insertion of the operculum occlusor muscles. The aim of this study is to describe Aluis spinettai gen. et sp. nov., from material collected in the Monte León, the Chenque, and the Puesto del Museo formations (early Miocene, Patagonia, Argentina). A. spinettai has erect bilaminar colonies, crenulated sutures between zooids, an extensive cryptocyst and spherical ovicells; gymnocyst, oral spines, and avicularia are absent. The new species exhibits a remarkable morphological convergence with a species of Aspidostoma from the early Miocene (Chenque Formation) of Patagonia. In some areas of the colony, the cryptocysts were pierced by circular drill holes made by an unknown predator. The stratigraphic distribution of A. spinettai ranges from â19 to 17 Ma (Burdigalian). Its presence suggests a correlation between the upper levels of the Monte León Formation and the lower levels of the Chenque Formation. The paleogeographic distribution of this new species spans at least 500 km along the southern Atlantic coast of South America. The living representatives of the Chaperiidae in the Southwest Atlantic do not seem related to A. spinettai. Fil: López Gappa, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Pérez, Leandro Martín. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina

This paper describes an integrated field, petrographic and geochemical study of the Puesto del Museo Formation, a poorly known unit that evidences a Cenozoic transgression at the southernmost Golfo San Jorge Basin. The most striking features of the Puesto del Museo Formation is its occurrence as restricted ~20 m-thick-outcrops composed exclusively of friable cross-stratified grainstones. We analyzed the sedimentary facies and facies associations in order to reconstruct the depositional setting. The petrographic characterization allows assessing the composition as a very homogeneous lithological succession dominated by skeletal grainstones. Geochemistry of trace elements (Mn, Sr, Rb, rare earth elements plus yttrium = REY), and stable isotopes (C and O) were used to characterize the grainstones compositionally, and to constrain environmental and climate conditions that controlled its deposition. The diagenetic environmental comprehension helped to the interpretations of the syn- and post-depositional conditions related to the grainstones. Finally, the stratigraphic position of the Puesto del Museo grainstones into the context of the basin is discussed. This succession can be correlated with the Patagonian marine event (i.e., Golfo San Jorge and Austral basins) that took place during the late Oligocene–early Miocene, related to an elevated global sea level controlled by glacio-eustatic conditions. Fil: Gómez Peral, Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina Fil: Raigemborn, María Sol. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina Fil: Richiano, Sebastián Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico de Geología y Paleontología; Argentina Fil: Arrouy, Maria Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina Fil: Odino Barreto, Andrea Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina Fil: Pérez, Leandro Martín. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina Fil: Sial, Alcides N.. Universidade Federal de Pernambuco; Brasil Fil: Ferreyra, Camila. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina

A Sr-isotope chronostratigraphy is presented for Miocene sediments deposited by the “Paranense” Sea along 1200 km of the southwestern Atlantic coast of Argentina and Uruguay. Numerical ages were obtained for shells of Aequipecten paranensis from the Argentinean Puerto Madryn Formation, Facies Balneario La Lobería, “Entrerriense Beds” of the Salado Basin, and Paraná Formation, and from the Camacho Formation (Uruguay). The 87Sr/86Sr ages fall into five age-groups that encompass the “Paranense” flooding in the latest Serravalian-Messinian interval. For the Puerto Madryn Formation, the ages span the latest Serravalian to the Tortonian and are stratigraphically coherent with the transgressive phase (11.9–10.4 Ma) and the regressive phase (10.2–9.82 Ma and 9.40–9.05 Ma) of that unit. Ages of 8.85–7.95 Ma for the “Entrerriense Beds” show them to be Tortonian while the Facies Balneario La Lobería, and the Paraná and Camacho formations span the age-range 7.50–6.00 Ma, comprising the Tortonian-Messinian interval. The regressive phase of the Puerto Madryn Formation, and the Facies Balneario La Lobería are respectively correlated with the basal and middle beds of the cliffs at Barranca Final, where the uppermost horizons of the Barranca Final Formation are exposed. The “Entrerriense Beds” are correlated with the “Cape Fairwheater Beds”. Dating the “Paranense” marine incursion permits a reappraisal of its paleogeography and differentiation of its deposits from those of the “Patagoniense” Sea. The flooding area was smaller than previously thought, with its northwestern-most boundary in the surroundings of the Santa Fe Province and its southernmost boundary in southern Santa Cruz Province. Moreover, the Paranaian Molluscan Bioprovince was coeval with the Valdesian Molluscan Bioprovince for 2.35 Ma and species included in the Aequipecten paranensis Zone lived for at least 5.90 Ma. Fil: del Río, Claudia Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Martinez, Sergio. Universidad de la República; Uruguay Fil: Mc Arthur, John. University College London; Estados Unidos Fil: Thirwall M,. University College London; Estados Unidos Fil: Pérez, Leandro Martín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina

The bryozoan genus Aspidostoma Hincks, 1881 has been regarded as the only representative of the Aspidostomatidae Jullien, 1888 in Argentina to date. Its type species, Aspidostoma giganteum (Busk, 1854), is presently distributed in the Magellanic Region (Argentina and Chile) and has been recorded in Oligocene and Miocene fossil deposits of Santa Cruz and Chubut, respectively. New material from San Julián (late Oligocene), Monte León (early Miocene), Chenque (early to middle Miocene), and Puerto Madryn (late Miocene) formations suggests, however, that A. giganteum is not represented in the fossil record. Material from Puerto Madryn Formation previously regarded as A. giganteum is here recognized as Aspidostoma roveretoi new species. Aspidostoma ortmanni Canu, 1904 is revalidated for the species from the San Julián Formation. Aspidostoma armatum new species and Aspidostoma tehuelche new species are introduced for material from the Monte León and Chenque formations, respectively. Aspidostoma incrustans Canu, 1908, from the early Miocene, is redescribed. Melychocella Gordon and Taylor, 1999, which differs from Aspidostoma in having vicarious avicularia and lacking a median ridge and a quadrangular process proximal to the opesia-orifice, is so far represented by three Paleogene species from the Chatham Islands (Southwest Pacific). The material from Monte León allowed us to transfer Aspidostoma flammulum Canu, 1908 to Melychocella, resulting in the new combination Melychocella flammula (Canu, 1908). Melychocella biperforata new species is described from the lower Miocene Monte León and Chenque formations. The presence of Melychocella in the Neogene of Patagonia extends its geographic distribution and its temporal range.UUID: http://zoobank.org/d84df2d8-cab2-4e74-82b8-7c67d938a58f

Platychelyna secunda sp. nov. is described based on material collected in the Monte León Formation, Patagonia, Argentina (early Miocene). This is the second species of Platychelyna Hayward and Thorpe to be described and the first fossil representative, expanding the stratigraphic range of the genus by ~20 Ma. P. secunda and P. planulata Hayward show similar geographic distributions in the southern tip of South America. Zooid size is ~50% larger in the recent species compared to the fossil one, which could be related to the cooling of the water masses in the Southwest Atlantic since the opening of the Drake Passage towards the end of the Oligocene. Fil: López Gappa, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Pérez, Leandro Martín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: Griffin, Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina

El objetivo de este trabajo es el análisis tafonómico del holotipo de Crossvallia unienwillia Tambussi, Reguero, Marenssi and Santillana, 2005, con el fin de incrementar el conocimiento acerca del registro fósil de vertebrados de la Formación Cross Valley, aflorante en el área central de la Isla Marambio (Seymour), Península Antártica. El análisis del estado preservacional de los restos de Crossvallia unienwillia ofrece importantes datos para las reconstrucciones paleoambientales y áreas depositacionales, claves para la comprensión de la historia evolutiva temprana de los pingüinos. Diferentes técnicas, incluyendo el estudio de secciones petrográficas, observaciones en MEB, detector de electrones secundarios, detector de electrones dispersos, difracción de rayos X y rayos X de energía dispersiva, fueron aplicados para distinguir las alteraciones bioestratinómicas de aquellas fósil-diagenéticas. Los restos de Crossvallia forman parte de una asociación típicamente marina, incluyendo además tiburones y macroinvertebrados. Los sedimentos portadores indican un ambiente de baja energía, ya sea por debajo del tren de olas, o bien protegido de la acción de las olas. En cualquiera de estos casos, las condiciones marinas iniciales cambiaron hacia otras con un flujo regular de material continental sedimentario. Crossvallia unienwillia fue una hembra buceadora, que atravesó varios periodos de muda antes de su muerte. Procesos bioestratinómicos consistentes con un bajo transporte y un rápido sepultamiento que habría prevenido la acción de procesos destructivos tales como la meteorización son inferidos para este caso. El enterramiento rápido favoreció la preservación de los elementos bajo condiciones anóxicas. La corrosión superficial, las fracturas y el relleno de cavidades internas, sugiere que los procesos destructivos fueron solo importantes luego del sepultamiento durante estadios telodiagenéticos. La ausencia de otros vertebrados fósiles en el Alomiembro Cross Valley C es el resultado de esos procesos, mientras que de manera contraria, el ambiente depositacional pareció haber sido óptimo. The purpose of this paper is to provide a taphonomic analysis of the holotype of Crossvallia unienwillia Tambussi, Reguero, Marenssi and Santillana, 2005, in order to improve the knowledge of the vertebrate record of the Cross Valley Formation, a unit exposed in the central area of Marambio (Seymour) Island, Antarctic Peninsula. Analyses of the preservational state of the skeleton assigned to Crossvallia unienwillia offer important data for palaeoenvironmental and depositional reconstructions, key for the understanding of the early evolutionary history of penguins. Different techniques, including petrographic sections, SEM observation, Secondary Electrons Detectors, backscattered electrons detectors, microanalysis for probe of electrons, and X-ray diffraction were applied in order to distinguish biostratinomic from fossil diagenetic damage. Fossil bones of Crossvallia are associated with a typical marine assemblage including shark remains and macroinvertebrates. The hosting mudstones suggest a low-energy environment either below the wave-base or protected from wave action. In any case initial marine conditions changed to other with regular influx of land-derived sedimentary material. Crossvallia unienwillia was a female diver that passed through several molting periods before death. Biostratinomic processes consistent with little transport and rapid burial which would have prevented the action of destructive processes such as weathering and carnivores or scavenging, are inferred. The rapid burial favored the initial preservation of the elements under anoxic conditions. The surficial corrosion, fractures, and the internal filling of the cavities, suggest that destructive processes were only important after final burial during the telodiagenetic stage. The absence of more vertebrate fossil remains in the Cross Valley C Allomember is the result of those destructive processes, whereas on the contrary the original depositional environment appears to have been optimal. Fil: Acosta Hospitaleche, Carolina Ileana Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina Fil: Pérez, Leandro Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina Fil: Marenssi, Sergio Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Geología; Argentina Fil: Reguero, Marcelo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleontología Vertebrados; Argentina

The bryozoan fauna from the South American Cenozoic is poorly known. The study of new material collected in the Monte León Formation (early Miocene), gave us the opportunity to describe four new species: Valdemunitella canui n. sp., Foveolaria praecursor n. sp., Neothoa reptans n. sp., and Calyptotheca santacruzana n. sp. Two of them (V. canui and C. santacruzana) were first recorded by F. Canu and interpreted as recent species from the Australian bryozoan fauna, but are herein described as new species. The stratigraphic range of Otionella parvula (Canu, 1904) is extended to the early Miocene. The present study emphasizes the close relationships between the South American Neogene bryozoan faunas and those of other Gondwanan sub-continents such as New Zealand and Australia. Fil: Pérez, Leandro Martín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina Fil: López Gappa, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentina Fil: Griffin, Miguel. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America., Facultad de Ciencias Naturales y Museo

The top of the Querales Formation is well exposed at the Quebrada Corralito section, 17 m thick, in northern Venezuela. The section, dominated by siliciclastic accumulations of fine-grained sediments, preserves one cycle of transgressive–regressive phases of the deltaic environments facing the marine platform. An X-ray analysis revealed kaolinite as the main clay mineral. The age ranges from late Early Miocene to early Middle Miocene—zones N8 to N9, Late Burdigalian to Langhian. The section shows low biodiversity, including eleven macroinvertebrate taxa and two ichnotaxa; at its base, it contains mostly plant debris and amber from the continent, thus revealing a continental source near the littoral zone. Its middle portion preserves macroinvertebrates from the littoral zone, but also including the cephalopod Aturia sp., transported by a hydraulic flow to an area of greater depth; these macroinvertebrates are absent from overlying sections, at a time in which the basin was flooded most. The X-ray diffraction on six rock samples revealed mainly the presence of quartz with calcite, subordinated plagioclase and traces of potassium feldspar. Other minerals that compose this stratigraphic section are pyrite, dolomite and siderite, but they are disseminated in a siltstone. The section is dominated by mudstone sediments. The succession is kaolinite in the most pure fraction, and in lesser proportion smectite and illite; the stratified illite–smectite, chlorite and chlorite–smectite are present in low quantity. The mineralogical components of a molluscan valve were also examined, showing abundant pyrite, and moderate amounts of siderite and dolomite. In a part of the section, we recorded a rich assemblage of calcareous microfossils with foraminifers, nannofossils and marine ostracods. In the foraminiferal assemblage, 99 % correspond to planktonic forms. Most macroinvertebrates from benthonic assemblages suggest that they may have inhabited a near-shore marine environment, and sporadically experienced storm transport to deeper, shelf waters. Fil: Pérez, Leandro Martín. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Perez Panera, Juan Pablo. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. YPF - Tecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Aguilera, Orangel A.. Universidade Federal Fluminense; Brasil Fil: Ronchi, Diana I.. YPF - Tecnología; Argentina Fil: Sánchez, Rodolfo. Municipio de Urumaco. Museo de Paleontología; Venezuela Fil: Manceñido, Miguel Oscar. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Paleozoología Invertebrados; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sánchez Villagra, Marcelo R.. Universitat Zurich; Suiza