Diversity of cingulate xenarthrans in the middle-late Eocene of Northwestern Argentina

The study of Paleogene mammals of intermediate and low latitudes has increased in the last decades and has been clearly demonstrated their importance in the comprehension of the evolution and faunistic changes outside Patagonia. The study of these faunas permits establishing new comparisons among contemporaneous faunistic associations, completing the distributional patterns, and evaluating evolutionary changes in the lineages in relation to climatic conditions prevailing in each of the different regions. In this work we study the diversity of Dasypodidae recovered from the Geste Formation (Northwestern Argentina). Bearing levels of Geste Formation were referred alternatively to a Barrancan subage of Casamayoran SALMA (middle Eocene, Lutetian-Bartonian) or a Mustersan SALMA (middle-late Eocene, Bartonian-Priabonian) on faunistic comparations with their equivalent in Patagonia, although absolute isotopic data indicates ca. 37-35 Ma (late Eocene, Priabonian). We described the following taxa of Dasypodidae: (i) Dasypodinae Astegotheriini: cf. Astegotherium sp., ?Prostegotherium sp., Parastegosimpsonia cf. P. peruana; (ii) Dasypodinae indet.; (iii) Euphractinae Euphractini: Parutaetus punaensis sp. nov.; (iv) Dasypodidae incertae sedis: Pucatherium parvum, Punatherium catamarcensis gen. et sp. nov. In comparison with other beds bearing Eocene cingulate faunas from Northwestern Argentina, Geste Formation presents the greatest diversity of dasypodids. This association is consistent with a late Eocene age and shows a taxonomic and biogeographic relevant features given by a unique specific composition: (i) it differs from that known for contemporaneous faunas from Southern latitudes and younger associations from more tropical areas; (ii) it includes genera with close affinities to those distant areas; (iii) it presents unique taxa typical from Eocene units exposed at Northwestern Argentina. This highlights the evolutionary and biogeographic meaning of the cingulate of the Geste Formation and supports the idea that the faunistic regionalization probably obeyed to latitudinal than to temporal factors.Facultad de Ciencias Naturales y Muse

Diversity of cingulate xenarthrans in the middle-late Eocene of Northwestern Argentina

The study of Paleogene mammals of intermediate and low latitudes has increased in the last decades and has been clearly demonstrated their importance in the comprehension of the evolution and faunistic changes outside Patagonia. The study of these faunas permits establishing new comparisons among contemporaneous faunistic associations, completing the distributional patterns, and evaluating evolutionary changes in the lineages in relation to climatic conditions prevailing in each of the different regions. In this work we study the diversity of Dasypodidae recovered from the Geste Formation (Northwestern Argentina). Bearing levels of Geste Formation were referred alternatively to a Barrancan subage of Casamayoran SALMA (middle Eocene, Lutetian-Bartonian) or a Mustersan SALMA (middle-late Eocene, Bartonian-Priabonian) on faunistic comparations with their equivalent in Patagonia, although absolute isotopic data indicates ca. 37-35 Ma (late Eocene, Priabonian). We described the following taxa of Dasypodidae: (i) Dasypodinae Astegotheriini: cf. Astegotherium sp., ?Prostegotherium sp., Parastegosimpsonia cf. P. peruana; (ii) Dasypodinae indet.; (iii) Euphractinae Euphractini: Parutaetus punaensis sp. nov.; (iv) Dasypodidae incertae sedis: Pucatherium parvum, Punatherium catamarcensis gen. et sp. nov. In comparison with other beds bearing Eocene cingulate faunas from Northwestern Argentina, Geste Formation presents the greatest diversity of dasypodids. This association is consistent with a late Eocene age and shows a taxonomic and biogeographic relevant features given by a unique specific composition: (i) it differs from that known for contemporaneous faunas from Southern latitudes and younger associations from more tropical areas; (ii) it includes genera with close affinities to those distant areas; (iii) it presents unique taxa typical from Eocene units exposed at Northwestern Argentina. This highlights the evolutionary and biogeographic meaning of the cingulate of the Geste Formation and supports the idea that the faunistic regionalization probably obeyed to latitudinal than to temporal factors.Facultad de Ciencias Naturales y Muse

Recent discovery of an argyrolagid (Mammalia, Metatheria) for the Marplatan stage (middle Pliocene-early Pleistocene) of northwestern Argentina

We present the first remains of an argyrolagid from the Uquía Formation (middle Pliocene-early Pleistocene; Marplatan) recovered at San Roque, Humahuaca, Jujuy Province, Argentina. The material is part of a microvertebrate fossil assemblage generated by trophic activity of predator birds that also includes amphibians, lizards, birds, rodents and didelphids. The remains represent three individuals and include fragments of maxilla and dentaries, and postcranial fragmentary bones (humeri, astragali, calcanei, and ungueal phalanges). The upper teeth show a simplified occlusal morphology, typical of this family. The most conspicuous features of lower teeth are: the presence of procumbent incisors, a mesiolabial expansion defining a shallow groove on m1, deep lingual groove absent on m1 and m2 but present on m3 and m4, m4 reduced with a deep labial groove and a shallow distal concavity. The morphology of lower molars (particularly, on m4 the deep labial groove and the distal shallow concavity) allows us to refer the material to Microtragulus bolivianus Hoffstetter and Villarroel. This species differs from other species of Microtragulus by: the absence of lingual groove on m1, labial groove of mesial lobe on m2, and lingual groove on m2, and the presence of larger m4 with a labial groove (M. reigi Simpson); its larger size, the deepest labial groove, and the presence of lingual groove on m3 and labial groove on m4 (M. catamarcensis [Kraglievich]); and by the absence of lingual groove on m1 and the presence of deeper labial grooves (M. rusconii Goin, Montalvo and Visconti). Rodents recorded in this assemblage (Microcavia, octodontids) are nowadays typical dwellers of dry and open areas, suggesting similar paleoenvironmental conditions for these levels of the Uquía Formation. The presence of Microtragulus bolivianus in western Bolivia and northwestern Argentina suggests that a continuous area of xeric conditions was already established in this region by the end of the Pliocene.Sesiones libresFacultad de Ciencias Naturales y Muse

Diversity of cingulate xenarthrans in the middle-late Eocene of Northwestern Argentina

The study of Paleogene mammals of intermediate and low latitudes has increased in the last decades and has been clearly demonstrated their importance in the comprehension of the evolution and faunistic changes outside Patagonia. The study of these faunas permits establishing new comparisons among contemporaneous faunistic associations, completing the distributional patterns, and evaluating evolutionary changes in the lineages in relation to climatic conditions prevailing in each of the different regions. In this work we study the diversity of Dasypodidae recovered from the Geste Formation (Northwestern Argentina). Bearing levels of Geste Formation were referred alternatively to a Barrancan subage of Casamayoran SALMA (middle Eocene, Lutetian–Bartonian) or a Mustersan SALMA (middle–late Eocene, Bartonian–Priabonian) on faunistic comparations with their equivalent in Patagonia, although absolute isotopic data indicates ca. 37–35 Ma (late Eocene, Priabonian). We described the following taxa of Dasypodidae: (i) Dasypodinae Astegotheriini: cf. Astegotherium sp., ?Prostegotherium sp., Parastegosimpsonia cf. P. peruana; (ii) Dasypodinae indet.; (iii) Euphractinae Euphractini: Parutaetus punaensis sp. nov.; (iv) Dasypodidae incertae sedis: Pucatherium parvum, Punatherium catamarcensis gen. et sp. nov. In comparison with other beds bearing Eocene cingulate faunas from Northwestern Argentina, Geste Formation presents the greatest diversity of dasypodids. This association is consistent with a late Eocene age and shows a taxonomic and biogeographic relevant features given by a unique specific composition: (i) it differs from that known for contemporaneous faunas from Southern latitudes and younger associations from more tropical areas; (ii) it includes genera with close affinities to those distant areas; (iii) it presents unique taxa typical from Eocene units exposed at Northwestern Argentina. This highlights the evolutionary and biogeographic meaning of the cingulate of the Geste Formation and supports the idea that the faunistic regionalization probably obeyed to latitudinal than to temporal factorsFil: Ciancio, Martin Ricardo. 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; ArgentinaFil: Herrera, Claudia Marcela Reina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Aramayo, Alejandro José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Payrola Bosio, Patricio Augusto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; ArgentinaFil: Babot, María Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del NOA. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Museo de Ciencias Naturales. Instituto de Bio y Geociencias del NOA; Argentin

Diversity of cingulate xenarthrans in the middle-late Eocene of Northwestern Argentina

The study of Paleogene mammals of intermediate and low latitudes has increased in the last decades and has been clearly demonstrated their importance in the comprehension of the evolution and faunistic changes outside Patagonia. The study of these faunas permits establishing new comparisons among contemporaneous faunistic associations, completing the distributional patterns, and evaluating evolutionary changes in the lineages in relation to climatic conditions prevailing in each of the different regions. In this work we study the diversity of Dasypodidae recovered from the Geste Formation (Northwestern Argentina). Bearing levels of Geste Formation were referred alternatively to a Barrancan subage of Casamayoran SALMA (middle Eocene, Lutetian-Bartonian) or a Mustersan SALMA (middle-late Eocene, Bartonian-Priabonian) on faunistic comparations with their equivalent in Patagonia, although absolute isotopic data indicates ca. 37-35 Ma (late Eocene, Priabonian). We described the following taxa of Dasypodidae: (i) Dasypodinae Astegotheriini: cf. Astegotherium sp., ?Prostegotherium sp., Parastegosimpsonia cf. P. peruana; (ii) Dasypodinae indet.; (iii) Euphractinae Euphractini: Parutaetus punaensis sp. nov.; (iv) Dasypodidae incertae sedis: Pucatherium parvum, Punatherium catamarcensis gen. et sp. nov. In comparison with other beds bearing Eocene cingulate faunas from Northwestern Argentina, Geste Formation presents the greatest diversity of dasypodids. This association is consistent with a late Eocene age and shows a taxonomic and biogeographic relevant features given by a unique specific composition: (i) it differs from that known for contemporaneous faunas from Southern latitudes and younger associations from more tropical areas; (ii) it includes genera with close affinities to those distant areas; (iii) it presents unique taxa typical from Eocene units exposed at Northwestern Argentina. This highlights the evolutionary and biogeographic meaning of the cingulate of the Geste Formation and supports the idea that the faunistic regionalization probably obeyed to latitudinal than to temporal factors.Facultad de Ciencias Naturales y Muse

New mandibular remains of Callistoe (Metatheria, Sparassodonta) reveal unexpected anatomical, functional, and evolutionary aspects of this carnivorous genus

We present a detailed description of the anatomy of the dentary and lower teeth of a new specimen of Callistoe vincei, a large carnivorous metatherian from the Eocene (?Ypresian) of northwestern Argentina. The recently collected specimen is a young adult represented by a partial right dentary with the canine, p1, roots of p3, and very well-preserved m1 to m4. The description includes a comparison with the holotype specimen, a much older individual, and other closely related large sparassodonts (e.g., Arminiheringia). The analysis of this new material allowed identifying plesiomorphic molar features in Callistoe, such as the presence of a reduced metaconid on the m3 and a tricuspated, basined talonid on m1–m3. We also described the mesowear facets in the lower dentition, showing that the self-sharpening facet typically present in extinct and extant placental and some marsupial carnivorous forms, was absent in Callistoe. The presence of a short-term cutting edge in the trigonid related to the thinness of the enamel layer, and the associated tooth wear susceptibility, were likely compensated by a dental mechanism (overeruption) to maintain occlusal contact among antagonist teeth. This process could explain the marked extrusion of the tooth roots observed in Callistoe as well as in other large closely related members of the group.Fil: Babot, María Judith. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Miguel Lillo; ArgentinaFil: Rougier, Guillermo Walter. University of Louisville; Estados UnidosFil: Garcia Lopez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Bertelli, Sara Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Herrera, Claudia Marcela Reina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Deraco, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Giannini, Norberto Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

Registro fósil de la Puna

Las referencias de restos fósiles de la Puna son escasas; las más diversasy abundantes incluyen mayormente fauna paleozoica constituida principalmente por trilobites, graptolites, conodontes, trazas y en menor medida se registran foraminíferos, braquiópodos, esponjas, moluscos, briozoos y cnidarios. Los datos florísticos paleozoicos son también escasos y no están analizados en detalle, a excepción de criptoesporas ordovícico-silúricas. Las rocas sedimentarias mesozoicas expuestas en la región están virtualmente desprovistas de elementos bióticos asociados. Escasos restos de cianobacterias, foraminíferos, ostrácodos,equinodermos, moluscos y peces fueron citados para depósitos jurásicos y cretácicos. El contenido paleontológico cenozoico incluye principalmente vertebrados del Eoceno tardío cuyo grupo más significativo y mejor conocido lo constituyen los mamíferos. Entre estos, los más diversos son los Metatheria y los euterios Notoungulata y Cingulata que en algunos casos indican un regionalismo marcado en relación a la fauna coetánea de unidades eocenas próximas, mientras que en otros evidencian una asociación de fauna relacionada a diversos taxones de distribución temporal y geográfica más amplia. Son también llamativas las huellas de aves mi ocenas y pleistocenas y los restos óseos de fauna pliocena y pleistocena. En el contexto regional, la Puna limita con provincias morfotectónicas muy ricas en contenido fósil; en este marco, la intensificación y sistematización de las prospecciones paleontológicas y elestudio detallado del material ya recuperado proveerá evidencia relevante para comprender o reinterpretar diversos aspectos de la evolución de parte de la biota sudamericana en estas latitudes.“The fossil record of the Puna”. Fossil references are scarce for the Puna; the most diverse and abundant materials include mainly Paleozoic fauna from Cambrian, Ordovician, Silurian, and Permian rocks represented by trilobits, graptolites, conodonts, and associated trace fossils. Other records include foraminifers, brachiopods, sponges, molluscs, bryozoans, cnidarians, and crinoids. The Punean paleofloristic records are scarce and poorly studied, except for Ordovician and Silurian cryptospores from western Puna. The Mesozoic sedimentary units are almost devoid of fossil content, with meager elements assigned to cyanobacteria, foraminifers, ostracods, echinoderms, molluscs, and fishes cited from the Jurassic and Cretaceous. The Cenozoic fossil data include mainly late Eocene vertebrates, among which the best known are mammals. The most diverse mammalian groups recorded are Metatheria and the eutherian Notoungulata and Cingulata (Xenarthra). Some of these clades exhibit some degree of regionalism in relation to the contemporary fauna of geographically close Eocene units. Others fossils reveal a faunistic association allied to geographically distant taxa. The Cenozoic record also includes Miocene and Pleistocene trace fossils assigned to aquatic birds and Pliocene and Pleistocene mammalian osseous materials. In a regional context, the Puna is bounded by morphotectonic provinces distinguished by their high paleontological content; the intensification and systematization of paleontological surveys and the detailed study of fossil material previously exhumed in this plateau will provide relevant evidence for understanding or reinterpreting diverse aspects of the evolution of the South American biota in these subtropical latitudes.Fil: Babot, María Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Fundación Miguel Lillo; ArgentinaFil: Aceñolaza, Guillermo Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Carrizo, Hugo Alfredo. Fundación Miguel Lillo; ArgentinaFil: Garcia Lopez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentin

Postcranial remains of basal typotherian notoungulates from the eocene of Northwestern Argentina

Notoungulates represent the most taxonomically diverse and temporally and geographically widespread group among South American native ungulates. Here, we analyze anatomical and systematic aspects of proximal tarsal bones recovered from the Lower and Upper Lumbrera formations (middle and late middle Eocene) in northwestern Argentina. We provide detailed descriptions, comparisons, and infer foot stances and range of movements for the taxa implicated. Material studied includes astragali belonging to the oldfieldthomasiid Colbertia lumbrerense (Lower Lumbrera Formation), a set of proximal tarsals referred as Typotheria indet. (Lower Lumbrera Formation), and tarsals (also including navicular and cuboid) of the informal taxon “Campanorco inauguralis” (Upper Lumbrera Formation). The comparison of the tarsals of Colbertia lumbrerense (middle Eocene of Argentina) with Colbertia magellanica (early Eocene of Brazil) reveals several differences including variations on the development and arrangement of articular facets, and the size of the dorsal astragalar foramen in the Argentinean species. The specimen of Typotheria indet. shows morphological affinities with basal interatheriid taxa. However, its larger size contrasting with the overall small body sizes of Eocene interatheriids precludes an indisputable taxonomic assignment. Concerning “Campanorco inauguralis”, our observations indicate that there is no morphological evidence for a close phylogenetic relationship with Mesotheriidae. It presents a “reversed alternating tarsus” condition, which is also observed in Leontiniidae, “Notohippidae”, Toxodontidae, and some typotherians. However, the spectrum of singularities exhibited by this form precludes the assessment of its relationships in the context of the Paleogene radiation of Typotheria and it is necessary to extend the comparison to Eocene notoungulates. Finally, in a morphofunctional context a plantigrade foot posture is inferred for the specimens here reported. These observations have the potential to provide functional proxies for paleoecological reconstructions to be applied to the study of the early radiation of these notoungulate faunas.Fil: Armella, Matías Alberto. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Garcia Lopez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Babot, María Judith. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Deraco, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Herrera, Claudia Marcela Reina. Fundación Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Saade, Luis Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Bertelli, Sara Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentin

New Cingulata (Mammalia, Xenarthra) from the Upper Lumbrera Formation (Bartonian, middle Eocene), Salta Province, Argentina

Nós descrevemos restos isolados de cingulado do Paleógeno da localidade de El Simbolar, Formação Lumbrera Superior (Bartoniano), sul da Província de Salta, noroeste da Argentina. O material consiste em numerosos osteodermos das bandas fixas, móveis e caudais. Os osteodermos têm tamanho grande, com uma figura principal de aspecto lageniforme, como em Utaetus buccatus, U. laxus, U. argos, ?U. deustus, Punatherium catamarcensis, e o eufractino basal Archaeutatus. A combinação de caracteres morfológicos, em adição ao seu grande tamanho, nos permite reconhecer uma nova espécie de “Utaetini” para o Paleógeno do noroeste da Argentina. Esta nova espécie de ?Utaetus representa o registro mais antigo para Euphractinae nesta região e fortalece a condição endêmica das faunas paleógenas no noroeste da Argentina.We describe isolated remains of a Paleogene cingulate from El Simbolar locality, Upper Lumbrera Formation (Bartonian), southern Salta Province, northwestern Argentina. The material consists of numerous fixed, movable, and caudal sheath osteoderms. The specimen has large-sized osteoderms, with a lageniform main figure, as in Utaetus buccatus, U. laxus, U. argos, ?U. deustus, Punatherium catamarcensis, and the basal euphractin Archaeutatus. The combination of morphological characters, in addition to its large size, allows us to recognize a new species of “Utaetini” for the Paleogene of northwestern Argentina. This new species of ?Utaetus represents the oldest record of Euphractinae in this region, and strengthens the endemic condition of its Paleogene faunas.Fil: Herrera, Claudia Marcela Reina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Esteban, Graciela Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Garcia Lopez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Deraco, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Babot, María Judith. Universidad Nacional de Tucuman. Facultad de Cs.naturales E Instituto Miguel Lillo. Centro de Investigaciones En Ecología Historica.; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Fundación Miguel Lillo; ArgentinaFil: del Papa, Cecilia Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Bertelli, Sara Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Giannini, Norberto Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

Primer ave del eoceno del noroeste de Argentina

A new fossil bird is described from the Upper Lumbrera Formation of Northwestern Argentina. Lumbrerornis rougieri gen. et sp. nov. is represented by three-dimensionally preserved elements of the hindlimb of a single individual. Morphological comparative studies and particular characters of the tibiotarsus suggest that the new species might be related to the extinct clades Palaeotididae and Geranoididae of the Northern Hemisphere, which were recently hypothesized to be Paleogene palaeognathous birds. However, the fragmentary preservation of the new fossil prevents a confident systematic position. The Upper Lumbrera Formation is a widely recognized fossiliferous unit with a very rich fauna of mammals and other vertebrates (e.g., fishes, crocodilians, turtles, snakes). This is the first record of a three-dimensionally preserved fossil bird from the Eocene of northwestern Argentina and thus provides fresh evidence of the Eocene faunas from the area and improves our understanding of the poorly known early Paleogene avifaunas from South America.Se describe una nueva ave fósil de la Formación Lumbrera Superior del Noroeste de Argentina. Lumbrerornis rougieri gen. et sp. nov. está representada por elementos del miembro posterior de un único individuo que se ha preservado tridimensionalmente. Estudios de morfología comparada y caracteres del tibiotarso sugieren que la nueva especie se relacionaría con los clados extintos Palaeotididae y Geranoididae del hemisferio norte, grupos que han sido recientemente hipotetizados como relacionados a aves paleognatas del Paleógeno. Sin embargo, la preservación fragmentaria del nuevo fósil impide una ubicación sistemática precisa. La Formación Lumbrera Superior es una unidad fosilífera ampliamente reconocida por una gran diversidad de mamíferos y otros vertebrados (ej., peces, cocodrilos, tortugas, serpientes). Éste es el primer registro de un ave preservada tridimensionalmente que constituye una nueva evidencia sobre la fauna del Eoceno del noroeste de Argentina y contribuye a un mayor conocimiento sobre la avifauna poco conocida del Paleógeno de América del Sur.Fil: Bertelli, Sara Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina. Fundación Miguel Lillo; Argentina. American Museum of Natural History; Estados UnidosFil: Giannini, Norberto Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina. American Museum of Natural History; Estados Unidos. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Garcia Lopez, Daniel Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Deraco, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Babot, María Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Fundación Miguel Lillo; ArgentinaFil: del Papa, Cecilia Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Armella, Matías Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Universidad Nacional de Catamarca. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Herrera, Claudia Marcela Reina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Mayr, Gerald. Senckenberg Forschungsinstitut; Alemani