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This study describes two new species of cheilostome bryozoans associated with gastropod shells from the Monte León Formation (Burdigalian, early Miocene), Argentine Patagonia. Burdwoodipora griffini sp. nov. is the second known species and the first fossil representative of the genus, whose geographic distribution is so far restricted to the Magellan region in the southern southwest Atlantic. it differs from the type species, B. paguricola, in lacking suboral adventitious avicularia in most autozooids. Odontoporella miocenica sp. nov. is morphologically very close to the type species, the Recent O. adpressa, from which it differs in having smaller zooids with fewer areolae and relatively wider orifices. The stratigraphic range of Odontoporella is here extended from the Pleistocene to the early Miocene. its geographic distribution includes southern south America, New Zealand, and New caledonia, suggesting an austral origin of the genus in the Paleogene of former Gondwana. The possible association of these two species with paguroid crabs is discussed. [ABSTRACT FROM AUTHOR]

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 of Jolietina and Parafigularia: J. victoria n. sp. and P. pigafettai n. sp., respectively. A fossil species of Figularia, F. elcanoi n. 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 of Jolietina: J. latimarginata (Busk, 1884) and J. pulchra Canu and Bassler, 1928a. The systematic position of some species previously assigned to Figularia is here discussed. Costafigularia n. gen. is erected, with Figularia pulcherrima Tilbrook, Hayward, and Gordon, 2001 as type species. Two species previously assigned to Figularia are here transferred to Costafigularia, resulting in C. jucunda n. comb. and C. tahitiensis n. comb. One species of Figularia is reassigned to Vitrimurella, resulting in V. ampla n. comb. The family Vitrimurellidae is here reassigned to the superfamily Cribrilinoidea. The subgenus Juxtacribrilina is elevated to genus rank. Inferusia is regarded as a subjective synonym of Parafigularia. Parafigularia darwini Moyano, 2011 is synonymized with I. taylori Kuklinski and Barnes, 2009, resulting in Parafigularia taylori n. 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 [ABSTRACT FROM AUTHOR]

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 replacement name for Taylorius Gordon, 2014 (Bryozoa), a secondary homonym of Taylorius Britton, 1960 (Arthropoda: Coleoptera). Here, we describe Taylorus patagonicus sp. nov. from the early Miocene of Argentine Patagonia, and two new living species from New Zealand, Taylorus microperforatus sp. nov. and Taylorus alatus sp. nov. These new finds extend the known range of Taylorus nom. nov. to areas formerly comprising the Gondwanan supercontinent. Cladistic analysis suggests that there is a basal divergence within Taylorus nom. nov. in which an extant lineage consisting of species from South Africa and New Zealand is the sister group to the remaining species. Two New Zealand fossil taxa, T. masoni and T. waiparaensis, were not recovered in an exclusively Zealandian clade. The early Miocene New Zealand species T. masoni nested with three Recent Zealandian species, this subclade being sister to a group comprising the remaining New Zealand species and that from Patagonia. These different lineages suggest that Taylorus nom. nov. originated in the Paleogene, perhaps in the early Oligocene or late Eocene. [ABSTRACT FROM AUTHOR]

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 fl ammulum Canu, 1908 to Melychocella, resulting in the new combination Melychocella fl ammula (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. [ABSTRACT FROM AUTHOR]

We present the first taphonomic analysis on basal sauropodomorph dinosaur remains from the Los Colorados Formation. We analyzed 22 bone samples with X-ray diffractometry, three of these in petrographic sections and one of them in SEM. In this article we recognize the taphonomic processes (biostratinomic and fossil-diagenetic) involved in the genesis of the 'La Esquina Local Fauna'. Regarding fossil diagenesis, it was possible to recognize the different processes that acted on the bone remains. In this sense, we analyzed different types of fracture present in the bones and their relationship with expansion generated by changes in the volume of minerals (for example, carbonates, gypsum and anhydrite). Finally, the importance of more taphonomic studies throughout the Los Colorados Formation is highlighted in order to better understand the vertebrate fossil record it contains. • Sauropodomorph bones were affected by different taphonomic processes. • At least three types of fractures associated with volume changes of minerals. • The fractures analyzed in the bones are of fossil-diagenetic origin. • The fossil record of vertebrate remains is found in well-developed overbank/floodplain deposits and rarely within fluvial channel facies. • Major bone loss can be explained by actual exhumation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The Cueva del Milodón (CdM, southern Chile), has been explored repeatedly since the end of the 19th century. Many institutions in the world house specimens from CdM, standing out the mylodontid sloths. Until now, 36 14C measurements were performed on these remains using equivalent methodologies, Gas Proportional Counter (GPC), Liquid Scintillation Counting (LSC) and Accelerator Mass Spectrometry (AMS). The goals of this work are to review published dates, report two new radiocarbon dates made by us, and discuss the occurrence of the mylodonts in southernmost South America in a glacial context and its possible coexistence with humans. Among the published 16 direct (hair, skin, bone) and 20 indirect (excrement) 14C dates, 13 and 18 are considered here as reliable, respectively. Dates considered unreliable presented several issues (transcription errors, duplicate dates, misidentified samples, etc.), being excluded from the analysis to avoid further misunderstandings. Two new 14C dates performed by us on pieces housed in the Museo de La Plata (skin - AMS) and (bone - LSC) were added, making a total of 33 valid dates. A remarkable amplitude in the radiocarbon ages of the mylodont remains in CdM is evidenced, showing a range of values from ∼14,000 BP to ∼9800 BP, since upper Pleistocene ("Tarantian") to early Holocene (Greenlandian). However, the direct dates of maximum confidence available show a strong modal representation in the Upper Pleistocene. Climate evidence available for this period indicates a complex interplay of deglaciation and brief cold reversals, but suggests that mylodonts could take advantage of their dense fur and thick skin, large body mass and suitability to live in caves to prosper in such cold and humid environments. Finally, evidence supporting coexistence of mylodonts and humans is briefly discussed. Image 1 • Mylodontid ground sloth mummified skin from Cueva del Milodón, Chile, was analized. • Two new radiocarbonic dates were performed on this remain. • Previous dates of ground sloth remains from the same place were reviewed. • More reliable dates suggest ground sloth presence around upper Pleistocene. • Paleoclimatic context was reviewed, as well as potential coexistence with humans. [ABSTRACT FROM AUTHOR]

Fossil remains of extinct mylodontine sloths have been discovered in numerous localities throughout the American supercontinent, but knowledge of them is still mainly centered on the Pleistocene forms rather than their Neogene relatives. In this contribution, previously unpublished cranial and postcranial materials herein ascribed to Glossotherium chapadmalense (Kraglievich), coming from the Pliocene Chapadmalal Formation (Province of Buenos Aires, Argentina), are presented. These remains are described and compared with those of other mylodontine species from South and North America, providing an exhaustive characterization of cranial morphology in G. chapadmalense and some preliminary insights into its postcranial anatomy. The results have revealed a unique combination of differences and similarities of this enigmatic species with the larger-sized representatives of Glossotherium. In addition, these materials allowed shedding light on the long-standing uncertainties regarding its taxonomic status, as this form has been alternately considered to belong to the genera Glossotherium or Glossotheridium over the last century. As a result, the genus Glossotherium was present, at least, at the Early–Late Pliocene transition in the Pampean region of Argentina, and is recorded by the Upper Pleistocene throughout the entire South American continent. The radiation of the Pleistocene species is associated with a consistent body mass increase that was probably a response to the cooling temperatures and higher predation pressure in South America during the Late Pliocene–Early Pleistocene. These phenomena were probably driven by the stable emergence of the Panamanian Isthmus around 3 Ma and the successive faunal turnover pulses of the Great American Biotic Interchange. [ABSTRACT FROM AUTHOR]

The family Inversiulidae, and its only genus Inversiula, are unique among cheilostome bryozoans owing to the reverse orientation of the operculum, which hinges distally instead of proximally. Inversiula currently includes four extant and one fossil species almost exclusively distributed in the Southern Hemisphere. A phylogenetic analysis of the Inversiulidae based on morphological characters was performed, showing the existence of two clades with contrasting development of the frontal shield. As a result of this analysis, Parainversiula gen. nov. is erected to contain inversiulid species with an umbonuloid frontal shield structure and fewer than 30 central spoked pores. Two poorly known fossil species from the early Miocene of Patagonia (Argentina), originally assigned to the genus Microporella, are here redescribed as Parainversiula sp. and P. chubutiana (Canu) comb. nov. The historical, time-calibrated biogeography of Inversiulidae was estimated using an event-based, multi-model quantitative analysis. The analyses estimated that Australasia was the ancestral area of Parainversiula and a dispersion of the genus into South America occurred between the late Eocene and Oligocene (c. 23–42 Ma), an event that could have been helped by the origin of the Antarctic Circumpolar Current. [ABSTRACT FROM AUTHOR]

Pelecanus paranensis sp. nov., a new pelican (Aves, Pelecanidae) from the marine Upper Miocene Paraná Formation, which crops out in the Province of Entre Ríos, Argentina, is described. This record constitutes the first report of a fossil pelican from Argentina and the southernmost from South America. The holotypical specimen consists of a very large and nearly complete pelvis, which is characterized by having the cristae iliacae dorsales continuous throughout its entire length and a large foramen acetabuli. The U-shaped morphology of the postacetabular section of the pelvis of the new species as well as the wide incisura sutura iliosynsacralis, allow to infer its phylogenetic position within the New World pelican species clade, showing a close relationship with the clade (P. occidentalis + P. thagus). A probable transAtlantic dispersal route for the ancestor of the New World pelicans is thus inferred. The inland Paranaense Sea, which flooded the South American Chaco-Paraná basin during the mid-Neogene, is proposed as a south-north pathway for ancestral forms of the clade (P. occidentalis + P. thagus). These regressive marine paleoenvironments of the Late Miocene may have acted as the evolutionary driver for the transition of pelican species from brackish or freshwater habitats to those inhabiting strictly marine coastlines. [ABSTRACT FROM AUTHOR]

We examine three avian remains from the Última Esperanza cave complex. This site is a Natural Monument situated along the flanks of Cerro Benítez, Magallanes Region of Chile. A tarsometatarsus (MLP 94-VIII-10-12) is assigned to Rhea pennata, and a humerus (MLP 94-VIII-10-111) to Phalacrocorax brasilianus. Both, R. pennata and P. brasilianu s, are currently distributed in the Magallanes Region, and their presence within the cave can be easily explained by the cut marks found on the tarsometatarsus, that evidence human consumption. The absence of traces on the humerus is not decisive in this regard, because the wings are not the most fleshy parts of the body and therefore, not the preferred piece by predators. It can represent the waste. A small bill (MLP 94-VIII-10-140) of a passerine bird belongs to a fresh bone and should be treated as contamination. • This contribution presents the first study of the Cueva del Milodón avian fossil record. • A humerus assigned to Phalacrocorax brasilianus and a tarsometatarsus of Rhea pennata, belong to species that occur in the area today. • The cut marks observed in Rhea pennata evidence anthropic interaction. • A bill from Cueva del Milodón belongs to a recent passerine bird and is considered contamination. [ABSTRACT FROM AUTHOR]

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 87 Sr/ 86 Sr 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. [ABSTRACT FROM AUTHOR]

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. • Puesto del Museo Fm can represent the southernmost mid-Cenozoic carbonates at the GSJB. • These grainstones deposits flooded a rocky shore composed of the Jurassic volcanites. • The cementation begun at the seafloor followed by vadose conditions. • Trace elements supported by facies analysis reveal shallow open marine environment. • Bioclasts and C-isotope may suggest it as part of the Patagoniense transgression. [ABSTRACT FROM AUTHOR]