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Two new species of Euathlus (Verhandlungen der Kaiserlich‐Königlichen Zoologisch‐Botanischen Gesellschaft in Wien, 1875, 25, 125) from Argentina are described. Euathlus ameghinoi sp. n. and Euathlus ventus sp. n. are the first records for the Patagonian Steppe. Here we used mitochondrial DNA (cox1) to perform the first molecular phylogeny of some representatives of the genus. In addition, we present the first description of the sexual behaviour of the genus. Both molecular and cladistic morphological analysis showed the genus Euathlus as monophyletic, and new species were recovered as sister groups. New species show new morphological variations of typical characters for the genus (e.g. tibial apophyses and palpal organs). [ABSTRACT FROM AUTHOR]

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En este artículo abordamos la conflictividad social en el Noreste de Chubut durante la última dictadura militar desde 1976 a 1982 para dar cuenta de cuales fueron los conflictos que se realizaron, que sujetos lo protagonizaron, quienes lo organizaron y de que forma el conflicto fue realizado, dentro de un análisis que incluye a lo que definimos como estructura socio-económica, comprendiendo a los conflictos como parte constitutivita de la sociedad. Partiendo del análisis del periódico Diario Jornada realizamos un estudio de tipo cualitativo y cuantitativo que nos permite construir ciclos y fases hacia dentro del período, permitiendo observar cómo se construyen las modificaciones dentro de la conflictividad dentro de los años signados por el devenir de la dictadura militar.

In a forest of Nothofagus pumilio (lenga) in northern Chubut, we found a stand affected by Notophorina sp. (Hemiptera, Psyllidae) with outstanding foliar symptoms. We assumed that it is about a peak of abundance, which is the first record in Argentinean Patagonia. Our aim was to characterize the stand and the health condition of affected trees related to the peak abundance of Notophorina sp. In a stand located at 42°41'36.06" S - 71°44'42.26" W, in the Parque Nacional Los Alerces (Chubut, Argentina), two samplings were carried out in an eighteen day period (T1, T2) during the summer (January and February) of 2020. A health survey was performed and Notophorina sp. abundance was evaluated. Thirty percent of the trees showed defoliation in T1 and this value increased to 50% in T2. The symptoms were chlorosis, necrosis, leaves curling and partial or total defoliation. At T2, the previously affected trees had smaller leaves (1.80±0.38 cm²) than those recently affected (3.79±0.38 cm²), while the leaves of the healthy trees were the largest (6.99±0.38 cm²). The specific leaf area was similar for trees with old and recent infestation (123.3±20.34 cm²/g vs. 159.27±20.34 cm²/g) and significantly higher in healthy trees (289.15±20.34 cm²/g). The population density decreased drastically between both samplings (87%). This study contributes to the bioecological background of Notophorina sp. in the Patagonian Andean region and assesses the effect on its hosts. [ABSTRACT FROM AUTHOR]

Over the centuries there have been a number of attempts, for economic, political and religious reasons, to create Welsh settlements overseas. The most successful of these, in terms of longevity at least, and perhaps the best known of all Welsh emigration ventures, was the establishment in 1865 of a Welsh Settlement in Patagonia, in what is now the Province of Chubut in Argentina, where perhaps as many as 5,000 of the inhabitants still speak Welsh fluently or have some ability with the language. The preservation of Welsh identity was central to the Patagonian project, which aimed to create a new Welsh-speaking, self-governing Wales overseas, founded on Christian and democratic principles. From the outset, songs played an important role in fostering the ideals that inspired the founders of the Settlement, ideals that would come progressively under threat as the Argentine government increasingly asserted its authority over the Settlement, promoting Argentinian identity and replacing Welsh with Spanish as the medium of education. This paper gives an overview of the development of the Welsh Settlement in Chubut down to the present day, focussing especially on the role of song in nurturing the dream of the Settlement’s founders.

En un bosque de lenga (Nothofagus pumilio) en el norte de Chubut, detectamos un rodal afectado por Notophorina sp. (Hemiptera, Psyllidae) con sintomatología foliar destacada. Asumimos que se trata de un pico poblacional de este succionador, por primera vez registrado en la Patagonia argentina. El objetivo de este trabajo fue caracterizar la situación sanitaria del rodal y de los árboles afectados, asociada con el pico poblacional de Notophorina sp. El estudio se llevó a cabo en un rodal situado a los 42°41’36.06’’ S - 71°44’42.26’’ O, dentro de la jurisdicción del Parque Nacional Los Alerces (Chubut, Argentina). Se efectuaron dos muestreos en el verano de 2020 (enero-febrero), en un período de dieciocho días (T1, T2); se realizó una prospección sanitaria y se cuantificó la abundancia de Notophorina sp. sobre las ramas de los árboles afectados. El 30% de los árboles presentó defoliación en T1, y este valor subió a 50% en T2. Los síntomas registrados consistieron en clorosis, necrosis, arrepollamiento de la lámina foliar y defoliación parcial o total. Al momento del segundo monitoreo, los árboles con infestación más antigua presentaron hojas de menor tamaño (1.80±0.38 cm2) que los infestados recientemente (3.79±0.38 cm2), mientras que las hojas de los árboles sanos fueron mucho más grandes (6.99±0.38 cm2). El área foliar específica fue similar entre árboles con infestación antigua y reciente (123.3±20.34 cm2/g vs. 159.27±20.34 cm2/g), pero significativamente menor que en los árboles sanos (289.15±20.34 cm2/g). La densidad poblacional del succionador descendió drásticamente entre ambos muestreos (87%). Este trabajo contribuye a generar antecedentes bioecológicos sobre Notophorina sp. en la región de los Andes patagónicos, y a dimensionar el efecto sobre sus hospederos.

A 209 m-thick sedimentary succession exposed at Estancia Redonda Chica locality (northeastern Patagonia, Argentina) includes both the Gaiman Formation (Early Miocene) and the Puerto Madryn Formation (Late Miocene). Based on the sedimentologic analysis, the Gaiman Formation is interpreted as accumulated in a marine inner shelf to shoreline environment, whereas an estuarine to terrestrial environment is interpreted for the Puerto Madryn Formation. Fifteen samples were processed and analyzed for diatoms, providing for the first time a micropaleontological record for these units, allowing us to go deeper into the paleoenvironmental interpretations. Fourteen diatom species, two diatom genera, and chrysophyte stomatocysts were identified. The dominant diatom elements among the samples are Paralia sulcata, Lemnicola hungarica, Cocconeis placentula, and Pseudopodosira sp., together with chrysophyte stomatocysts. Paleoecological information drawn from diatom assemblages is consistent with paleoenvironmental interpretations based on sedimentological analysis for both units. However, diatom analysis for the Gaiman Formation suggests a strong freshwater influence in an inner shelf environment, which went unnoticed by utilizing other proxies. We suggest a high-productivity marine zone may have developed as a consequence of nutrient supply from rivers favoring diatom growth. This could explain the unique great abundance of macroinvertebrates and marine vertebrates preserved in the sedimentary succession. [ABSTRACT FROM AUTHOR]

Over the centuries there have been a number of attempts, for economic, political and religious reasons, to create Welsh settlements overseas. The most successful of these, in terms of longevity at least, and perhaps the best known of all Welsh emigration ventures, was the establishment in 1865 of a Welsh Settlement in Patagonia, in what is now the Province of Chubut in Argentina, where perhaps as many as 5,000 of the inhabitants still speak Welsh fluently or have some ability with the language. The preservation of Welsh identity was central to the Patagonian project, which aimed to create a new Welsh-speaking, self-governing Wales overseas, founded on Christian and democratic principles. From the outset, songs played an important role in fostering the ideals that inspired the founders of the Settlement, ideals that would come progressively under threat as the Argentine government increasingly asserted its authority over the Settlement, promoting Argentinian identity and replacing Welsh with Spanish as the medium of education. This paper gives an overview of the development of the Welsh Settlement in Chubut down to the present day, focussing especially on the role of song in nurturing the dream of the Settlement's founders. [ABSTRACT FROM AUTHOR]

Clams belonging to the genus Corbicula are considered one of the most harmful freshwater invaders with strong economic and ecological impacts. In South America, they were first detected in 1979 in the Río de La Plata estuary and since then they have rapidly spread throughout the north of Argentina. To the south, the Corbicula clam began appearing in the Colorado (~ 38°S) and Negro River (~ 40°S) basins around 1997–1999, and in the Limay and Neuquén Rivers (~ 38°S) around 2005. Almost twenty years later, this invasive clam reached the Chubut River (Chubut Province, Argentina). Here, we report for the first time the presence of Corbicula in the Chubut River (43.29° S), which represents the southernmost record of this invasive bivalve in the world. The most likely introduction pathway for the Corbicula clam in the Chubut River is ballast water associated with an estuarine port. Special attention is now required to detect the range of the invasion along the Chubut River basin and adjacent river basins such as Chico River to evaluate the ecological effects and the potential economic impacts on the industry. [ABSTRACT FROM AUTHOR]

Copyright of Agronomía & Ambiente is the property of Universidad de Buenos Aires. Facultad de Agronomia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This case study analyzes processes of contentious action in rejection of so-called “mega-mining” deployed on a subnational scale in Argentina from 2019-2021. These processes respond to a new stage in the cycle of social conflict over environmental issues in twenty-first century Argentina. This stage is configured through citizen resistance in different provinces with repertoires of convergent struggle, particularly against state mining policy. This renewed policy promoted by the national government in coordination with provincial governments and transnational corporations takes place in a context of socio-economic, environmental and health crises exacerbated by the outbreak of the COVID-19 pandemic. Based on a technocratic vision of society-nature articulations that clash with aspects of the current environmental legal system in Argentina, this model generates multiterritorial tensions (political, social, and cultural) in diverse subnational areas. The objective of the article is to understand the transformations of the actor dynamics around state mining policy in this context, including diverse and complex civil-social and political-institutional strategies. [ABSTRACT FROM AUTHOR]

The early diversification of caimanines is one of the least understood aspects of the evolutionary history of Crocodylia. The Palaeogene Argentinian caimanine record is extremely relevant because it provides key information on the early history of the clade. Most of the Palaeocene South American species are only or mainly known from partial lower jaws. Among the oldest Argentinian caimanines, Notocaiman stromeri (middle Palaeocene, Las Violetas Formation, Chubut Province) and Eocaiman palaeocenicus (lower Palaeocene, Salamanca Formation, Chubut Province) are represented by a partial left dentary and a fairly complete lower jaw, respectively. Notocaiman stromeri, has been phylogenetically interpreted from an alligatorid closely related to Eocaiman to an indeterminate eusuchian, but a modern anatomical revision of this species is lacking. Here, we redescribe in detail the only known specimen of Notocaiman stromeri (PVL 752) to revise its taxonomy and phylogenetic relationships. We concluded that Notocaiman and Notocaiman stromeri are nomina dubia and we refer PVL 752 to Eocaiman cf. E. palaeocenicus. Our phylogenetic analysis found Eocaiman palaeocenicus as the sister taxon to the Eocaiman cavernensis + Eocaiman itaboraiensis clade. Thus, here we reduce the alpha taxonomic diversity of alligatorids in the Palaeogene of South America but reinforce a geographically broad diversification of the genus Eocaiman, from the Palaeocene to the Eocene/Miocene in this continent. [ABSTRACT FROM AUTHOR]

The genus Ctenomys includes a high number of taxa, with at least ten species from Patagonia and three recently described species for northeastern Chubut Province (Argentina). Ctenomys sociabilis is a social species of the genus Ctenomys and is currently distributed in the surrounding area of Sierra Cuyin Manzano (Neuquén Province), with a recently extinct population that occurred in Laguna Nahuelquir (Cushamen, Chubut Province). Molecular analyses have placed C. sociabilis at the base of Ctenomys clade, as the sister species to all other Ctenomys. Based on a morphological assessment (qualitative and quantitative) and DNA sequencing, we describe a new species of Ctenomys from Esquel, Chubut Province. Phylogenetic analysis shows the new species to be closely related to C. sociabilis, with evidence of solitary behavior. This new species is the first reported to be closely related phylogenetically to Ctenomys sociabilis at the base of the Ctenomys phylogeny. We provide anatomical comparisons between the new species and other species of Ctenomys from Patagonia, especially C. sociabilis. [ABSTRACT FROM AUTHOR]

Por más de tres décadas el Laboratorio de Paleontología de Vertebrados de la Universidad Nacional de la Patagonia San Juan Bosco ha trabajado de forma sistemática en afloramientos cretácicos del centro sur de Chubut y norte de Santa Cruz. Durante todo este tiempo contribuyó al conocimiento de la dinámica paleoecológica de la fauna de vertebrados, particularmente dinosaurios. El trabajo y el esfuerzo, no solo permitieron incrementar el conocimiento, sino también la interacción con colegas e instituciones nacionales y extranjeras y la formación de recursos humanos. Asimismo, el laboratorio por medio de nuevas líneas de investigación y proyectos continúa trabajando con el objetivo principal de contribuir al desarrollo de la Paleontología en general y la Paleoherpetología en particular de la Argentina.

We describe the history and characterize the unions that integrate the workers of the processing on land of the Argentine fishing industry. The Sindicato Obrero de la Industria del Pescado (SOIP) in the province of Buenos Aires, and the Sindicato de Trabajadores de la Industria de la Alimentación (STIA) in the Patagonia, represent these workers.We are interested in recognizing their specificities, their paths and the reasons that explain the regional fragmentation of the union representation of this working group. We focus the observation in the port city of Mar de Plata and in northeastern Chubut (core key fishing in Argentina). We work with interviews, bibliographic systematization and journalistic, officials, unions and business sources. It is evidenced that the territorial division creates difficulties to conquer their labor claims, at the same time that organizational transformations are highlighted in the work process (due to changes in the target species) and of the gender composition in some of the unions.

El autor hace consideraciones y brinda más datos detallados sobre las delimitaciones y transiciones entre estas regiones botánicas de Argentina.

Se registró por primera vez el comportamiento de homing en Chaetophractus villosus. Se capturaron 33 individuos de C. villosus y se liberaron a diferentes distancias en Península Valdés, Chubut, Argentina. Del total de individuos, el 30 % regresó al punto captura dentro de los 12 días desde la liberación. El tiempo de recaptura aumentó de manera no linear respecto a la distancia, por lo que los puntos de liberación podrían estar fuera de su área de acción. El regreso al sitio de captura posiblemente se debe a que los peludos reconozcan a este sitio como fuente de recursos alimenticios.

With the aim to better understand the timing and geological evolution of the late Cenozoic stratigraphic record of the onshore, western Valdés Basin in northeast Chubut province (Patagonia, Argentina), we perform sedimentological, stratigraphic, and zircon U–Pb geochronologic analyses. The study includes the terrestrial Early Miocene Trelew Member of the Sarmiento Formation, the shallow marine Early Miocene Gaiman Formation, the shallow marine to estuarine Late Miocene Puerto Madryn Formation, and the Plesitocene fluvial conglomerates of the Rodados Patagónicos. Based on our data set, together with the recognition of relevant stratigraphic surfaces, we divide the succession into stratigraphically bounded units and define three cycles of sedimentation. The Lower Cycle rests on top of Surface 1, which comprise a long hiatus including the entire Oligocene Epoch. This cycle is in turn divided into two subunits separated by the transgressive, ravinement Surface 2. The Lower Cycle is separated from the overlying Middle Cycle (=Puerto Madryn Formation) by the flat and regionally extensive Surface 3. Finally, the latter is separated from the Upper Cycle (=Rodados Patagónicos) by Surface 4, a complex surface at the base of gravel deposits forming several terrace levels. Maximum depositional ages calculated from 10 zircon U–Pb samples indicate the succession between surface 1 and 4 extends from 21.5 to 2.7 Ma (Aquitanian-Piacenzian). The Lower Cycle is restricted to the 21.5–16 Ma interval (Aquitanian-Burdigalian); the Middle Cycle between 12 and 2.7 Ma (latest Serravalian-Piacenzian), with most of the new and previous ages clustering in the Tortonian; whereas the Upper Cycle is restricted to the Pleistocene. Although most of the analyzed sediments show fresh volcanic glass particles, older zircon ages are dominant, representing detrital components with a dominant peak of Permian-aged grains, with subordinated Devonian, Jurassic, Cretaceous, and Paleogene peaks. We interpret the analyzed succession as a condensed section compared to the offshore Valdés Basin depocenter area. Sedimentation in the study area was controlled by periods of slow subsidence, probably related to thermal subsidence and sediment compaction in the depocenter. Two main sources of sediments for the analyzed succession are envisaged: one represented by explosive volcanism located either in the Andes or in the North Patagonian Massif, the other through erosion of older rocks surrounding the North Patagonian Massif where late Paleozoic plutonic rocks are abundant. Particularly for the Middle and Upper cycles, an increase in Mesozoic contribution suggests erosion from sediments of the Cañadón Asfalto Basin. The new ages and stratigraphic analyses here reported are of major relevance for the integration of the onshore and offshore stratigraphies of the Valdés Basin which is key to connect the geologic evolution of the Andean and passive margin areas of southern South America. They are also of major relevance for the calibration of fossil communities, particularly for the abundant and diverse marine vertebrates preserved in the Burdigalian Gaiman Formation. • Zircon U–Pb ages and stratigraphic descriptions are provided for Neogene strata. • Results indicate three Neogene depositional cycles in the onshore Valdés Basin. • The Gaiman Formation is isotopically dated for the first time. • Late Paleozoic zircons are dominant, puzzling the provenance interpretations. [ABSTRACT FROM AUTHOR]