Paleontología Research Papers - Academia.edu (original) (raw)

PALEOENVIRONMENTAL MEANING OF THE PRESERVED FAUNA IN THE TREMEMBÉ FORMATION, TAUBATÉ BASIN, SÃO PAULO, BRAZIL This work comprised the study of the Tremembé formation of Taubaté Basin, São Paulo state. Basin analysis studies were based... more

Exceptionally preserved fossils provide crucial insights into extinct body plans and organismal evolution. Molluscs, one of the most disparate animal phyla, radiated rapidly during the early Cambrian period (approximately 535–520 million... more

Exceptionally preserved fossils provide crucial insights into extinct body plans and organismal evolution. Molluscs, one of the most disparate animal phyla, radiated rapidly during the early Cambrian period (approximately 535–520 million years ago (Ma)). The problematic fossil taxa Halkieria and Orthrozanclus (grouped in Sachitida) have been assigned variously to stem-group annelids, brachiopods , stem-group molluscs or stem-group aculiferans (Polyplacophora and Aplacophora), but their affinities have remained controversial owing to a lack of preserved diagnostic characters. Here we describe a new early sachitid, Calvapilosa kroegeri gen. et sp. nov. from the Fezouata biota of Morocco (Early Ordovician epoch, around 478 Ma). The new taxon is characterized by the presence of a single large anterior shell plate and polystichous radula bearing a median tooth and several lateral and uncinal teeth in more than 125 rows. Its flattened body is covered by hollow spinose sclerites, and a smooth, ventral girdle flanks an extensive mantle cavity. Phylogenetic analyses resolve C. kroegeri as a stem-group aculiferan together with other single-plated forms such as Maikhanella (Siphogonuchites) and Orthrozanclus; Halkieria is recovered closer to the aculiferan crown. These genera document the stepwise evolution of the aculiferan body plan from forms with a single, almost conchiferan-like shell through two-plated taxa such as Halkieria, to the eight-plated crown-group aculiferans. C. kroegeri therefore provides key evidence concerning the long debate about the crown molluscan affinities of sachitids. This new discovery strongly suggests that the possession of only a single calcareous shell plate and the presence of unmineralised sclerites are plesiomorphic (an ancestral trait) for the molluscan crown.

A new aglaspidid arthropod, Chlupacaris dubia gen. et sp. nov., is described from the Pusgillian (lower Ashgill, Upper Ordovician) Upper Tiouririne Formation near Erfoud, southeastern Morocco. Although disarticulated, careful documenting... more

A new aglaspidid arthropod, Chlupacaris dubia gen. et sp. nov., is described from the Pusgillian (lower Ashgill, Upper Ordovician) Upper Tiouririne Formation near Erfoud, southeastern Morocco. Although disarticulated, careful documenting of the tergites allows a reconstruction of the exoskeleton to be made. Although somewhat trilobite-like in appearance, the lack of facial sutures, a well-defined axis with articulating half-rings and a pygidium clearly prove Chlupacaris gen. nov. is not a trilobite. An interesting feature is the presence of a hypostome in this non-trilobite arthropod. In contrast to other aglaspidids usually considered to be carnivorous, a filter-feeding mode of life is proposed for Chlupacaris gen. nov., based on the strongly vaulted cephalon, subvertical orientation of the hypostome and less strongly vaulted trunk. Chlupacaris gen. nov. is probably most closely related to the atypical aglaspidid Tremaglaspis unite from the Tremadoc (Lower Ordovician) of the U.K., but it can also be tentatively linked to the problematic Lower Cambrian arthropods Kodymirus vagans and Kockurus grandis from the Czech Republic. The relevance and validity of previous definitions and of possibly significant characters used for identifying aglaspidids are evaluated, and as a result, a new combination of characters diagnosing Aglaspidida is proposed. Contrary to previous reports, it is suggested that aglaspidids are probably more closely related to trilobites than they are to chelicerates. This notion may be supported by the shared possession of a mineralised cuticle, a possibly similar number of cephalic appendages, and the presence of a hypostome in some forms, although this last character may alternatively be homoplastic.

La presente compilación, presenta las ponencias realizadas en el III Congreso Nacional
de Paleontología, realizado en un formato virtual del 30 de setiembre al 02 de octubre
2020. Lima, Perú

Los fósiles despertaron admiración y curiosidad en los naturalistas durante siglos, confiriendo al estudio de la vida del pasado uno de los temas más apasionantes de las Ciencias Naturales. Reconstruir ese pasado se ha convertido en la... more

Los fósiles despertaron admiración y curiosidad en los naturalistas durante siglos, confiriendo al estudio de la vida del pasado uno de los temas más apasionantes de las Ciencias Naturales. Reconstruir ese pasado se ha convertido en la meta de numerosos científicos, quienes se ocupan de descubrir y rescatar evidencias, aportando pequeñas piezas a un gran rompecabezas y cada nueva pieza ofrece nuevas respuestas, aunque también nuevos interrogantes... Caminando… invita a despertar el interés por las Ciencias Naturales, a través de la paleontología y la evolución faunística en la región Pampeana. La guía está organizada en cuatro módulos, incluyendo actividades, que nos introducen en el mundo de la paleontología y su historia en Argentina. Recorremos los millones de años de historia de la vida en la Tierra. Conocemos la megafauna pleistocena pampeana y las hipótesis sobre su extinción. Finalmente, discutimos la relación e importancia de los museos y las comunidades locales y el valor pat...

Plusieurs Lagerstätten à échinodermes ont été découverts au cours des dix dernières années dans l'Ordovicien supérieur de l'Anti-Atlas oriental (Tafilalt occidental, Maroc). Ces niveaux ont livré des assemblages particulièrement riches et... more

Plusieurs Lagerstätten à échinodermes ont été découverts au cours des dix dernières années dans l'Ordovicien supérieur de l'Anti-Atlas oriental (Tafilalt occidental, Maroc). Ces niveaux ont livré des assemblages particulièrement riches et diversifiés d'échinodermes. La préservation exceptionnelle de ces organismes témoigne d'un enfouissement rapide et in situ de communautés benthiques particulièrement denses constituées quasi-exclusivement d'échinodermes. Trois assemblages sont décrits : Bou Nemrou (Sandbien basal), piste de Jorf (Sandbien supérieur) et enfin, Tizi n'Mouri (Katien supérieur). L'intérêt scientifique majeur de ces faunes (implications paléoécologiques et paléogéographiques) est brièvement présenté. Enfin, la préservation de ces gisements, qui constituent un élément majeur du patrimoine paléontologique du Sud marocain, est abordée. Late Ordovician echinoderm Lagerstätten from the eastern Anti-Atlas (Morocco): an example of exceptional scientific heritage worthy of protection. Abstract. In the last ten years, several Late Ordovician echinoderm Lagerstätten have been discovered in the eastern Anti-Atlas (western Tafilalt) of Morocco. These levels have yielded extremely rich and diverse echinoderm assemblages. The exquisite preservation of most organisms suggests rapid and in-situ burial of large, particularly dense benthic communities largely dominated by echinoderms. Three « starfish beds » are briefly described: Bou Nemrou (earliest Sandbian), piste de Jorf (late Sandbian), and Tizi n'Mouri (late Katian). The major scientific relevance of these faunas is outlined herein (for example their palaeoecological and palaeogeographical implications). Finally, the conservation of these levels, which represent a major piece of the palaeontological heritage of southern Morocco, is discussed.

Exceptionally preserved fossils yield crucial information about the evolution of Life on Earth. The Fezouata Biota from the Lower Ordovician of Morocco is a Konservat-Lagerstätte of major importance, and it is today considered as an... more

Exceptionally preserved fossils yield crucial information about the evolution of Life on Earth. The Fezouata Biota from the Lower Ordovician of Morocco is a Konservat-Lagerstätte of major importance, and it is today considered as an 'Ordovician Burgess Shale.' This biota was discovered only some 15 years ago, but geological studies of the area date back to the beginning of the 20th century. Pioneering geological investigations lead to the discovery of Ordovician strata in the Anti-Atlas (1929) and ultimately resulted in their formal subdivision into four main strat-igraphic units (1942). In the Agdz area, the presence of fossiliferous Tremadocian (Lower Ordovician) strata was suspected as early as 1939, but only definitively confirmed in 1955. In the 1960s–1990s, Jacques Destombes provided the first detailed biostratigraphic framework for the Lower Ordovician of the Anti-Atlas, and collected thousands of fossils that were subsequently described in a series of monographs. In the early 2000s, exceptionally preserved fossils were discovered in the Fezouata Shale (Tremadocian–late Floian) in the central Anti-Atlas by Mohamed 'Ou Saïd' Ben Moula. This biota, now known as the Fezouata Biota, is of utmost importance, for it demonstrates the extent in the fossil record of non-biomineralising animals typical of the 'Cambrian Explosion' into the Ordovician, during the 'Great Ordovician Biodiversification.' Although most components are still in need of formal descriptions, a fairly good picture of the composition and organisation of this biota, and how it contributes to our understanding of the early evolution of metazoan communities, can now be depicted. Moreover, recent studies have substantially clarified the biostratigraphical and palaeoenvironmental context of the Fezouata Shale, and are now being followed up by detailed investigations of the taphonomy, geochemistry and micropalaeontology of this unique Konservat-Lagerstätte. These efforts will soon greatly benefit from the recovery of fresh, unweathered samples from drill cores.

The Weeks Formation in Utah is the youngest (c. 499 Ma) and least studied Cambrian Lagerstätte of the western USA. It preserves a diverse, exceptionally preserved fauna that inhabited a relatively deep water environment at the offshore... more

The Weeks Formation in Utah is the youngest (c. 499 Ma) and least studied Cambrian Lagerstätte of the western USA. It preserves a diverse, exceptionally preserved fauna that inhabited a relatively deep water environment at the offshore margin of a carbonate platform, resembling the setting of the underlying Wheeler and Marjum formations. However, the Weeks fauna differs significantly in composition from the other remarkable biotas of the Cambrian Series 3 of Utah, suggesting a significant Guzhangian faunal restructuring. This bioevent is regarded as the onset of a transitional episode in the history of life, separating the two primary diversifications of the Early Paleozoic. The Weeks fossils have been strongly affected by late diagenetic processes, but some specimens still preserve exquisite anatomical details. Supplementary material: a supplementary text (material and methods), four supplementary tables (compositions of the lower and upper Weeks faunas, structure of the upper Weeks fauna, and results of the similarity analyses), and a supplementary data file (generic presence/absence matrix) are available at https://doi.

La biota ediacárica representa uno de los mayores hitos en la historia evolutiva del planeta, pues contiene algunas de las primeras formas de vida animal pluricelular macroscópica bien conocida en el registro fósil y que presenta gran... more

La biota ediacárica representa uno de los mayores hitos en la historia evolutiva del planeta, pues contiene algunas de las primeras formas de vida animal pluricelular macroscópica bien conocida en el registro fósil y que presenta gran diversidad morfológica e interacciones ecológicas complejas, además de poseer integrantes microscópicos de gran relevancia evolutiva como los posibles primeros animales triploblásticos. Su posición estratigráfica corresponde con el final del Neoproterozoico, tiempo de aparición en el registro fósil de algunos de los primeros animales eumetazoos. La mayoría de los planes corporales de los organismos macroscópicos del Ediacárico no tienen equivalentes modernos e incluyen simetrías triradiales, octoradiales y fractales. La biota ediacárica vio su final al evolucionar los primeros organismos macrodepredadores con exoesqueletos que luego dominarían los ecosistemas del Fanerozoico.

We report the southernmost record of Bison latifrons in North America. This is the first record for the species in Oaxaca (Mexico), and for the Transmexican Volcanic Belt morphotectonic province; the known geographic distribution range of... more

We report the southernmost record of Bison latifrons in North America. This is the first record for the species in Oaxaca (Mexico), and for the Transmexican Volcanic Belt morphotectonic province; the known geographic distribution range of Bison latifrons is extended in more than 447 km, from Te-quixquiac in the State of Mexico to central Oaxaca. This finding comes from a new fossiliferous locality at the municipality of San Dionisio Ocotepec, located in the Central Valleys region of the state of Oaxaca, Mexico. The associated fauna includes: Mammuthus columbi, Equus cf. E. convers-idens, and Bison sp. By the presence of bison as well as mammoth, a Rancholabrean land mammal age (Late Pleistocene) is assigned to the fossil fauna. In addition, we performed a proboscidean mesowear analysis as well as a low magnification microwear analysis (35x) to the dental elements of the mammoth. Our findings suggest that the mammoth individual was a grazer. Due to the mammoth's feeding habits and the habitat described for Mexican samples of bison and horses, we concluded that during the Late Pleistocene, San Dionisio Ocotepec was dominated by open grassland in the lowlands. This new fossil site and its fauna contribute to improve the knowledge of the Rancholabrean in southern Mexico, and particularly in the Central Valleys of Oaxaca. This improves our understanding of the biotic and climatic changes during the foundation of the Holocene.

En México existen más de 800 localidades Pleistocénicas con presencia de mamíferos, ubicadas principalmente en el Cinturón Volcánico Trans-Mexicano, las cuales representan sitios que han contribuido al conocimiento de la evolución de la... more

En México existen más de 800 localidades Pleistocénicas con presencia de mamíferos, ubicadas principalmente en el Cinturón Volcánico Trans-Mexicano, las cuales representan sitios que han contribuido al conocimiento de la evolución de la megafauna del Pleistoceno en México. Particularmente, en Michoacán, la mayoría de los yacimientos fosilíferos de vertebrados se localizan en la Cuenca de Cuitzeo y los estudios paleontológicos hechos en esta área son primordialmente de tipo taxonómico y sólo muy pocos tienen un enfoque paleoecológico. De tal modo, el presente trabajo tiene como objetivo estudiar la fauna fósil del nuevo yacimiento de Ciudad Universitaria (UMSNH), ubicado en Morelia, dentro de la subcuenca Charo, que forma parte de la Cuenca de Cuitzeo, con la finalidad de aportar datos que corroboren la preferencia alimenticia y de hábitat de las especies encontradas, además de recabar información acerca del paleoambiente del sitio; utilizando para ello el método de isótopos estables de (δ 13 C y δ 18 O). Los resultados muestran cinco facies estratigráficas que sugieren diferentes ambientes sedimentarios. La fauna fósil se encontró en una biofacies fluviolacustre, y pertenece a tres diferentes ordenes, familias y géneros (Mammuthus columbi, Equus sp., Bison sp.). Además, la presencia de Bison sp. indica una edad Rancholabreano para este yacimiento fosilífero. Los análisis de isótopos estables δ 13 C y δ 18 O sugieren una dieta mixta (C 3/4 ) para el M. columbi y una dieta pacedora (C 4 ) para el Equus sp., por lo que se podría deducir para la zona un ambiente heterogéneo, es decir con vegetación de zonas cerradas (bosques) y abiertas (pastizales y/o praderas) conteniendo una proporción más o menos similar de pastos, herbáceas, arbustos y árboles.

Sinopsis sobre los registros fosilíferos de la Región Lambayeque, destacando los fósiles representativos y la estratigrafía representativa.

Se hace resumen del papel de los cambios climáticos en la historia de los pueblos. Particularmente de los pueblos mesoamericanos. Se relata el tránsito de los clovis hasta el Valle de Anáhuac. Se explica la relación de los cambios... more

Se hace resumen del papel de los cambios climáticos en la historia de los pueblos. Particularmente de los pueblos mesoamericanos.
Se relata el tránsito de los clovis hasta el Valle de Anáhuac. Se explica la relación de los cambios climáticos con la civilización. Se alerta sobre el calentamiento actual y sus futuros impactos.
Se explican las diferencias entre la visión de los pueblos originarios y los pueblos occidentales.

Castillejo del Bonete es un lugar sagrado de la Cultura de las Motillas, compuesto por varios túmulos, edificios y co-rredores con orientaciones astronómicas. Fue estratégicamente construido para monumentalizar una cueva que se encuentra... more

Castillejo del Bonete es un lugar sagrado de la Cultura de las Motillas, compuesto por varios túmulos, edificios y co-rredores con orientaciones astronómicas. Fue estratégicamente construido para monumentalizar una cueva que se encuentra en el borde meridional de la Meseta Sur, sobre un corredor natural de paso entre Andalucía, Levante y la Meseta. La cueva fue utilizada como cámara sepulcral. En el interior de la Galería 3 se encuentran restos humanos, piezas de ajuar y dos estelas funerarias. Este trabajo presenta el estudio de detalle de una de ellas. La estela funeraria con fósiles de Castillejo del Bonete es un registro único hasta la fecha. La muestra es una biocalcarenita con briozoos, bivalvos pectínidos y microfósiles característicos de un medio marino. Se trata de un bloque tallado sobre caliza fo-silífera alóctona. Los estudios realizados permiten afirmar que la pieza procede de los materiales del Mioceno medio de la provincia de Albacete. Las piezas arqueológicas depositadas aquí, tras su vida útil, fueron puestas al servicio de un ritual creado en torno a los ancestros y a un culto solar que perduró desde el Calcolítico hasta la Edad del Bronce, en los inicios de la jerarquización social al sur de la Meseta. //
SUMMARY Castillejo del Bonete is a sacred place of the Motillas Culture, that consists of several tumuli, buildings and corridors with astronomical orientations. It was strategically built to monumentalize a cave located at the southern edge of the Southern Plateau, on a natural corridor of passage between Andalusia, Levante and the Meseta. The cave was used as a burial chamber. There are human remains, archaeological pieces and two limestone funerary steles inside Gallery 3. This work presents the detailed study of one of them. The funerary stele with fossils from Castillejo del Bonete is a unique record up to date. The sample is a biocalcarenite with bryozoans, scallop bivalves and microfossils characteristic of a marine environment. It is a block carved on allochthonous fossiliferous limestone. The studies carried out allow us to affirm that the piece comes from middle Miocene of the province of Albacete. The archaeological pieces deposited here, after their useful life, were put to the service of a ritual created around the ancestors and a solar cult that lasted from the Chalcolithic to the Bronze Age, at the beginning of the social hierarchy in the South of the Meseta.

Four distinct echinoderm Lagerstätten have recently been discovered in the Upper Ordovician of the eastern Anti-Atlas, Morocco. They have yielded hundreds of exquisitely preserved specimens. Their taphonomy and associated lithology both... more

Four distinct echinoderm Lagerstätten have recently been discovered in the Upper Ordovician of the eastern Anti-Atlas, Morocco. They have yielded hundreds of exquisitely preserved specimens. Their taphonomy and associated lithology both suggest rapid, in situ burial. Here we discuss the diverse range of assemblages represented and their significance to the diversity of echinoderms in the Lower Palaeozoic. The oldest assemblage (Izegguirene Formation, lowermost Caradoc) is dominated by eocrinoids, large ophi-uroids, and mitrate stylophorans associated with rare crinoids. It shows strong similarities with slightly older faunas described from the underlying Ouine-Inirne Formation (Llandeilian) in the Central Anti-Atlas. The second assemblage (lower part of the Lower Ktaoua Formation, lower-middle Caradoc) is composed of eocrinoids (Cardiocystites) and small ophiuroids (encrinasterid indet.). The third assemblage was collected in the upper part of the Lower Ktaoua Formation (lowermost Ashgill). This 'starfish' bed is dominated by ophiuroids and large solutes, associated with common diploporites and rhombiferans, and rare crinoids and mitrates. Finally, the youngest assemblage (lower part of Upper Tiouririne Formation, lower Ashgill) has yielded abundant remains of edrioasteroids and rhombiferans.

The Carboniferous eurypterid Eurypterus dumonti STAINIER, 1917 from Mechelen-aan-de-Maas (Maasmechelen), Belgium is redescribed and assigned to the genus Adelophthalmus. It is diagnosed as having a raised triangle of unknown function,... more

The Carboniferous eurypterid Eurypterus dumonti STAINIER, 1917 from Mechelen-aan-de-Maas (Maasmechelen), Belgium is redescribed and assigned to the genus Adelophthalmus. It is diagnosed as having a raised triangle of unknown function, dorsally on opisthosomal segment 7 and a carapace articulating laterally against the second opisthosomal segment. Earlier assignments of this species to the genus Unionopterus, based on the carapace shape figured in the original description (STAINIER 1917), are incorrect and the existence of a Carboniferous eurypterid with the characteristics described for Unionopterus must be questioned. The appendages in A. dumonti are completely exposed and provide an unrivalled insight into the number of appendage podomeres in the genus; this species is interpreted to have a podomere count consistent with most other eurypterids. Small pustules previously thought to be cuticle sculpture are here interpreted as diagenetic``dumb-bells'' (see BRIGGS & WILBY 1996) following microbial activity on the carcase prior to fossilisation. Thesè`dumb-bells'' are the oldest non-marine record of this diagenetic feature. A number of other features are also interpreted differently from the original description. Possible lineages within the Adelophthalmus clade are identified, A. dumonti is probably closely related to A. imhofi (Czech Republic) and A. moyseyi (United Kingdom).

The INTERNATIONAL FOSSIL PLANT NAMES INDEX (IFPNI) was first launched in May, 2014 as a data base of fossil names of plants, algae, fungi, allied prokaryotic forms (formerly treated as algae and Ñyanophyceae in particular), algae-related... more

The INTERNATIONAL FOSSIL PLANT
NAMES INDEX (IFPNI) was first launched
in May, 2014 as a data base of fossil names
of plants, algae, fungi, allied prokaryotic
forms (formerly treated as algae and
Ñyanophyceae in particular), algae-related
protists and fossil microproblematica
(so-called ambiregnal organisms) published
in using binary nomenclature. The goal of
the IFPNI was also to compile and maintain
a comprehensive literature based record of these fossil scientific names and bank of
author names in palaeobotany. In modern
plant science there was no previously
comprehensive united index of recorded
fossil forms of algae, cyanobacteria and
related prokaryotic microorganisms
(interpreted in the past as algae), fungi and
plants, which were all described since early
XIX century up to our days.

ENG: Paleohistological study and ontogenetic series of skeletal remains of four different sirenians of the Torreforta's paleontological site (Tarragona), from the middle Miocene. // CAT: Estudi paleohistològic i sèrie ontogènica de restes... more

ENG: Paleohistological study and ontogenetic series of skeletal remains of four different sirenians of the Torreforta's paleontological site (Tarragona), from the middle Miocene. // CAT: Estudi paleohistològic i sèrie ontogènica de restes òssies de quatre individus diferents de sirenis provinents del jaciment paleontològic de Torreforta (Tarragona), del Miocè mitjà. // ESP: Estudio paleohistológico y serie ontogénica de restos óseos de cuatro diferentes individuos de sirenios provenientes del yacimiento paleontológico de Torreforta (Tarragona), del Mioceno medio.

Una ricerca sui resti rinvenuti nella Buca della Jena di Roselle da componenti della Società Naturalistica Speleologica Maremmana e studiati nel Dipartimento di Scienze della terra dell'Università degli Studi di Firenze

Los fósiles son restos de organismos que vivieron en tiempos geológicos pasados y que cuentan con una antigüedad de por lo menos 10 mil años, pero ¿conoces cuáles son los fósiles más importantes del Estado de Puebla? Esta obra te acompaña... more

Los fósiles son restos de organismos que vivieron en tiempos geológicos pasados y que cuentan con una antigüedad de por lo menos 10 mil años, pero ¿conoces cuáles son los fósiles más importantes del Estado de Puebla? Esta obra te acompaña a un recorrido a través de la historia geológica de Puebla y de sus sitios fosilíferos más relevantes (San Salvador Patlanoaya, Los Reyes Metzontla, Mazatepec, San Felipe Otlaltepec, San Juan Raya, San Martín Atexcal, Cantera Tlayúa, Huehuetla, Santiago Mitepec, Los Ahuehuetes, Pie de Vaca, Valsequillo y Santa Cruz Nuevo) para que los conozcas y comprendas la importancia de los mismos.