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Mallines are Patagonian wetlands characterized by permanent waterlogging on its soils, sustaining small shallow lakes that hosts a vast biodiversity. In these ecosystems, aquatic plants (i.e. macrophytes) develop different life forms adapted to humid conditions, allowing them to regulate the physical and chemical conditions of the mallin. A distinctive characteristic of Patagonia is the exponential west-east decrease in rainfall, which generates three biozones: forest, ecotone and steppe. These biozones have been typified using landform plants, but whether macrophytes assemblages are related to each biozone or not has not been evaluated yet. The aim of this work is to compare the attributes of the macrophyte and wetlands landform plants community in each biozone. During the 2013-2014 austral Summer, 20 shallow lakes were sampled in the west province of Chubut, assessing macrophyte richness and physical and chemical water variables. Macrophytes were classified according to their life forms, origin, and its diversity was calculated. A total of 62 taxa were determined, most of them corresponding to the Cyperaceae, Poaceae and Ranunculaceae families. The steppe exhibited alkaline pH values, and higher conductivity and soluble reactive phosphorus (SRP) than the ecotone and the forest. High SRP values favored the abundance of macrophytes and macroalgae. However, three sites were eutrophic, exhibiting high chlorophyll a and total phosphorus values. Those sites showed higher abundances of macroalgae and emerging macrophytes. The sampled shallow lakes would act as reservoirs of macrophyte diversity at both local and regional scales. Thus, understanding the relationships among macrophytes and environmental variables could be useful for the mallines biodiversity conservation plans.

Fil: Williams Subiza, Emilio Adolfo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Centro de Investigacion Esquel de Montana y Estepa Patagonica. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigacion Esquel de Montana y Estepa Patagonica; Argentina

Given the multiple stressors affecting freshwater ecosystems and the limited resources devoted to their management, effective conservation of freshwater biodiversity requires regional prioritization. Patagonian wetlands are essential for regional biodiversity and the economy, but they are still far from reaching global conservation targets and many of them could disappear due to climate change. Our study aimed at prioritizing wetlands based on aquatic and terrestrial biodiversity, their conservation status and vulnerability to climate change. First, we identified 43 priority wetlands containing all aquatic biodiversity collected in 82 Patagonian wetlands located over a 1500 km north–south gradient, by using the software Marxan. Then, we ranked within priority wetlands according to their conservation status (low priority if they were already protected; medium priority if not), importance for terrestrial biodiversity conservation (high priority) and vulnerability to climate change. Highly ranked priority wetlands in National Parks (low priority), contained diverse wetlands (57% aquatic taxon richness), including a large proportion of rare species (33%). High priority wetlands are oases of water in an arid and semiarid steppe, containing not only a large proportion of the aquatic biodiversity, but also acting as a refuge for terrestrial flora and fauna. Different management actions are proposed according to wetland priority level (e.g. fencing, creation of artificial ponds), and since 20% of medium priority and 36% of high priority wetlands are expected to disappear by 2050, their inclusion in conservation or restoration plans needs to be carefully evaluated.

Gripopterygidae is a diverse family of stoneflies, Plecoptera, distributed in the Southern Hemisphere. It has been traditionally divided into five subfamilies, but the monophyly of most of these is not supported by molecular the more comprehensive molecular analysis of the order. To test the monophyly of Antarctoperlinae, and to establish the phylogenetic position of a new Gripopterygidae species, we performed a morphological cladistic analysis including 38 morphological characters and 27 terminal taxa, with representatives of the four subfamilies present in South America and three Austroperlidae. Based on published information, we rooted the tree with Penturoperla barbata, Austroperlidae. As a result, Antarctoperlinae was recovered as polyphyletic, with Vesicaperla kuscheli and Plegoperla punctata, two members of the subfamily, placed outside the clade that includes the nine remaining genera of Antarctoperlinae. Vesicaperla also falls outside the family in previous molecular analysis. Based on this evidence, it should not be placed in Antarctoperlinae. Plegoperla punctata, known only from the type series, possesses many missing entries in our data matrix. Based on this, it seems convenient to maintain its subfamilial placement. In the tree obtained, the potential new species nests together with Pehuenioperla llaima. We thus accept it as a member of Pehuenioperla and describe it as P. microptera sp. nov Fil: Pessacq, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Duarte Tacio. Universidade de Sao Paulo; Brasil Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina

Pesticides are important contributors to the global freshwater biodiversity crisis. Among pesticides, neonicotinoids are the best-selling class of agricultural insecticides and are suspected to represent significant risks to freshwater and terrestrial ecosystems worldwide. Despite growing recognition that neonicotinoid impacts may be modified by the presence of additional stressors, there is limited information about their interactions with other agricultural stressors in freshwater ecosystems. We conducted an outdoor pond-mesocosm experiment to investigate the individual and interactive effects of nutrients, fine sediment, and imidacloprid (a neonicotinoid insecticide) inputs on freshwater community structure (density, diversity, and composition of zooplankton and benthic invertebrates) and ecosystem functioning (ecosystem metabolism, primary production, and organic matter decomposition). We hypothesized antagonistic nutrient-imidacloprid, and synergistic sediment-imidacloprid interactions, affecting aquatic invertebrate communities. The three stressors had significant individual and interactive effects on pond ecosystems. The insecticide neutralized the positive effects of nutrient additions on benthic invertebrate richness and mitigated the negative effects of sediment on zooplankton communities (antagonistic interactions). Moreover, we observed compensatory responses of tolerant benthic invertebrates, which resulted in reversal interactions between sediment and imidacloprid. Furthermore, our observations suggest that imidacloprid has the potential to increase net ecosystem production at environmentally relevant concentrations. Our findings support the hypothesis that the impacts of imidacloprid may be modified by other agricultural stressors. This has important implications on a global scale, given the widespread use of these pesticides in intensive agricultural landscapes and the growing body of literature suggesting that traditional pesticide assessment frameworks, based on laboratory toxicity tests alone, may be insufficient to adequately predict effects to complex freshwater ecosystems.

Knowledge of immature habitats is an important focus for investigations of mosquito community ecology, and may improve our understanding of how environmental variables increase risk of mosquito-borne diseases by influencing the distributions and abundances of species. In Patagonia region, where climatic and ecological factors could be only borderline suitable for mosquito development, relatively little is known about larval ecology. The present study focuses on associations of environmental conditions in natural aquatic habitats with abundances of mosquito species that have colonized such habitats in Patagonia. We described the mosquito community composition within 26 natural temporary pools, and assessed the general relationships between environmental variables (pH, water temperature, conductivity, salinity, dissolved oxygen, aquatic plant cover and main nutrients) and larval abundances using redundancy analysis (RDA). Additionally, we compiled monthly climate data and vegetation indices for each larval habitat, and estimated the probability of presence for two of the most abundant species, describing through generalized linear models (GLM) the environmental, climatic and landscape variables-probability of occurrence relationships. Seven species belonging to the genera Culex and Aedes were identified, with Culex apicinus, Cx. acharistus and Aedes albifasciatus being the most abundant. Mean larval densities were low (6.8 ± 2.8 larvae/dip), and the highestspecies richness and larval densities were recorded in northern and central areas. Aedes albifasciatus, a species of sanitary importance, was widely distributed, being the only one collected south of the 45th parallel of S latitude. RDA indicated that aquatic conductivity, pH, water depth, dissolved oxygen, ammonia and soluble reactive phosphorous accounted for the main part of the variation in the species composition. According to GLMs, wind speed was thevariable that best described the presence of Ae. albifasciatus, and the probability of finding this species was positively associated with high wind speed values. On the other hand, the EVI vegetation index was the only variable included in the Cx. apicinus model, whereby there was a great probability of presence in arid areas with lower EVI values. Our results enhance our knowledge of larval habitat ecology under the extreme environmental conditions of Patagonia and will guide future efforts to understand how multiple effects can affect mosquito ecology and public health at higher latitudes. Fil: Grech, Marta Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Manzo, Luz Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Laurito, Magdalena. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentina Fil: Claverie, Alfredo Ñancuche. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Ludueña Almeida, Francisco. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Almiron, Walter Ricardo. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina

The efficiency of biodiversity assessments and biomonitoring studies is commonly challenged by limitations in taxonomic identification and quantification approaches. In this study, we assessed the effects of different taxonomic and numerical resolutions on a range of community structure metrics in invertebrate compositional data sets from six regions distributed across North and South America. We specifically assessed the degree of similarity in the metrics (richness, equitability, beta diversity, heterogeneity in community composition and congruence) for data sets identified to a coarse resolution (usually family level) and the finest taxonomic resolution practical (usually genus level, sometimes species or morphospecies) and by presence-absence and relative abundance numerical resolutions. Spearman correlations showed highly significant and positive associations between univariate metrics (richness and equitability) calculated for coarse- and finest-resolution datasets. Procrustes analysis detected significant congruence between composition datasets. Higher correlation coefficients were found for datasets with the same numerical resolutions regardless of the taxonomic level (about 90%), while the correlations for comparisons across numerical resolutions were consistently lower. Our findings indicate that family-level resolution can be used as a surrogate of finer taxonomic resolutions to calculate a range of biodiversity metrics commonly used to describe invertebrate community structure patterns in New World freshwater wetlands without significant loss of information. However, conclusions on biodiversity patterns derived from datasets with different numerical resolutions should be critically considered in studies on wetland invertebrates. Fil: Marques Pires, Mateus. Universidad de Vale do Rio dos Sinos; Brasil Fil: Grech, Marta Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Stenert, Cristina. Universidad de Vale do Rio dos Sinos; Brasil Fil: Maltchik, Leonardo. Universidad de Vale do Rio dos Sinos; Brasil Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia "San Juan Bosco". Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: McLean, Kyle I.. United States Geological Survey; Estados Unidos Fil: Kneitel, Jamie M.. California State University; Estados Unidos Fil: Bell, Douglas A.. East Bay Regional Park District; Estados Unidos Fil: Greig, Hamish S.. The University Of Maine (the University Of Maine); Fil: Gagne, Chase R.. The University Of Maine (the University Of Maine); Fil: Batzer, Darold P.. University of Georgia; Estados Unidos

Fil: Epele, Luis Beltrán. Centro de Investigación Esquel de Montaña y Estepa Patagónica (CONICET-UNPSJB), Esquel, Chubut, Argentina 2Facultad de Ciencias Naturales y Ciencias de la Salud, UNPSJB, Esquel, Chubut, Argentina 3Freshwater Ecology, Hydrology and Management group (FEHM), Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain Fil: Dos Santos Daniel Andrés. Instituto de Biodiversidad Neotropical, CONICET –UNT, Cúpulas Universitarias S/N, Cátedra de Biología Animal, Facultad de Ciencias Naturales e IML, UNT, Yerba Buena, Tucumán, Argentina Fil: Sarremejane, Romain. INRAE, UR-RiverLy, Centre de Lyon-Grenoble Auvergne-Rhône- Alpes, Villeurbanne Cedex, France Fil: Grech, Marta Gladys. Centro de Investigación Esquel de Montaña y Estepa Patagónica (CONICET-UNPSJB), Esquel, Chubut, Argentina 2Facultad de Ciencias Naturales y Ciencias de la Salud, UNPSJB, Esquel, Chubut, Argentina Fil: Macchi, Pablo Antonio. Universidad Nacional de Río Negro, Instituto de Investigación en Paleobiología y Geología, Río Negro, Argentina Fil: Manzo, Luz María. Centro de Investigación Esquel de Montaña y Estepa Patagónica (CONICET-UNPSJB), Esquel, Chubut, Argentina Fil: MIserendino, María Laura. Centro de Investigación Esquel de Montaña y Estepa Patagónica (CONICET-UNPSJB), Esquel, Chubut, Argentina 2Facultad de Ciencias Naturales y Ciencias de la Salud, UNPSJB, Esquel, Chubut, Argentina Fil: Bonada, Núria. Freshwater Ecology, Hydrology and Management group (FEHM), Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona, Barcelona, Spain Fil: Cañedo-Argüelles, Miguel. Serra-Hunter fellow, Freshwater Ecology, Hydrology and Management group (FEHM), Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Institut de Recerca de l'Aigua (IdRA), Universitat de Barcelona, Barcelona, Spain Aim: To assess the relative importance of wind intensity and direction in explaining wetland invertebrate metacommunity organization. Location: Seventy-eight wetland ponds in Patagonia (Argentina) covering a study area of 3.5 × 10 5 km 2 . Time period: Ponds were sampled once between 2006 and 2014. Major taxa studied: One hundred and fifty-eight taxa of wetland aquatic invertebrates. Methods: We generated two beta diversity matrices (based on flying and non-flying invertebrates) and six predictor matrices, including three environmental distance matrices, a topographic distance between ponds, and two wind pairwise matrices differing in wind speed. Using Moran spectral randomization of Mantel (MSR-Mantel) tests (which account for spatial autocorrelation), we assessed the relationship between the response and the predictor matrices. We used a network-constrained version of the nestedness metric based on overlap and decreasing fill (NODF), to assess if wind anisotropy (i.e., direction-dependent) affected community nestedness among ponds. Results: Flying dispersers’ dissimilarity was significantly explained by environmental variables, whereas non-flying invertebrates’ dissimilarity was not significantly explained by any of the distances tested. When wind direction was ignored, wind speed had a negligible effect on both types of communities, whereas when it was considered a consistent nested pattern emerged, with the eastern ponds (downwind) communities being subsets of those from the western ponds (upwind). Aim: To assess the relative importance of wind intensity and direction in explaining wetland invertebrate metacommunity organization. Location: Seventy-eight wetland ponds in Patagonia (Argentina) covering a study area of 3.5 × 10 5 km 2 . Time period: Ponds were sampled once between 2006 and 2014. Major taxa studied: One hundred and fifty-eight taxa of wetland aquatic invertebrates. Methods: We generated two beta diversity matrices (based on flying and non-flying invertebrates) and six predictor matrices, including three environmental distance matrices, a topographic distance between ponds, and two wind pairwise matrices differing in wind speed. Using Moran spectral randomization of Mantel (MSR-Mantel) tests (which account for spatial autocorrelation), we assessed the relationship between the response and the predictor matrices. We used a network-constrained version of the nestedness metric based on overlap and decreasing fill (NODF), to assess if wind anisotropy (i.e., direction-dependent) affected community nestedness among ponds. Results: Flying dispersers’ dissimilarity was significantly explained by environmental variables, whereas non-flying invertebrates’ dissimilarity was not significantly explained by any of the distances tested. When wind direction was ignored, wind speed had a negligible effect on both types of communities, whereas when it was considered a consistent nested pattern emerged, with the eastern ponds (downwind) communities being subsets of those from the western ponds (upwind).

Ecological regions are areas of similar nature in terms of environmental features. Examination of the correspondence between organismal assemblage structure and function at different levels of spatial scale is crucial regarding pond conservation, especially in unexplored areas as continental austral Patagonia, where the extensive sheep breeding has been the historical land use. We assessed relationships between invertebrate assemblages and environmental characteristics at local (hydrogeomorphology and genesis) and landscape scale (phytogeographical and biozones) on 20 isolated wetland ponds (Southern Patagonia, Argentina). Additionally, we recognized best environmental predictors of invertebrate community attributes using generalized linear models (GLM). Most ponds displayed low anthropogenic stress since most of them were far from urban and rural settlements. Even though a few sites showed strong oxygen depletion (n = 3), most were well oxygenated (>85%, >11 mg/l). Also, ponds had low ammonia and soluble reactive phosphorus contents (>60%, 25 µg/l). A total of 80 invertebrate taxa were found, with Insecta and Oligochaeta displaying the highest richness. Cyanallagma interruptum (Anisoptera), Parapsectrocladius sp. and Parachironomus sp. (Chironomidae) were the most abundant taxa. Redundancy Analysis (RDA) showed that local environmental factors greatly explained the abundance patterns of invertebrates. In addition, variance partitioning analyses displayed that taxa responded more strongly to pond genesis (7% of variation) than to the other levels of spatial scale analyzed. Structural and functional attributes of communities (metrics) also showed that genesis (local scale) resulted a reliable predictor. Thus, the community composition changed according to fluvial, glacigenic, mass removal or anthropogenic origin of the ponds. Our results suggest that ponds across the austral continental Patagonia area appeared as crucial reservoirs of invertebrate biodiversity sustaining several endemic taxa. However, the expansion of new agricultural and land use practices in surrounding areas could impact negatively on pond integrity. Conservation programs should include major constrains at both, local and landscape scale, in which part of the physical complexity is driving by pond origin. Fil: Manzo, Luz Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Grech, Marta Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Kandus, Patricia. Universidad Nacional de San Martín. Instituto de Investigación en Ingeniería Ambiental; Argentina Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina

Climate change that affects biota in lower latitudes may presage biotic assemblages of higher latitudes. Macroinvertebrate assemblages in depressional wetlands may be especially sensitive to climate change because weather‐related precipitation and evapotranspiration are dominant ecological controls on habitats, and organisms of depressional wetlands are temperature‐sensitive ectotherms. We aimed to better understand how wetland macroinvertebrates assemblages were structured according to geography and climate. To do so, we contrasted aquatic‐macroinvertebrate assemblage structure (family‐level) between subtropical and temperate depressional wetlands of North and South America using presence‐absence data from 264 of these habitats across the continents and more‐detailed relative‐abundance data from 56 depressional wetlands from four case study locations (North Dakota and Georgia in North America; southern Brazil and Argentinian Patagonia in South America). Both data sets roughly partitioned wetland numbers equally between the two climatic zones and between the continents. We used ordination methods (PCA and NMDS) and tests of multivariate dispersion (PERMDISP) to assess the distribution and the homogeneity in variation in the composition of macroinvertebrate assemblages across climates and continents, respectively. We found that macroinvertebrate assemblage structures in the subtropical depressional wetlands of North and South America were similar to each other (at the family level), while assemblages in the North and South American temperate wetlands were unique from the subtropics, and from each other. Tests of homogeneity of multivariate dispersion indicated that family‐level assemblage structures were more homogeneous in wetlands from the subtropical than temperate zones. Our study suggests that ongoing climate change may result in the homogenization of macroinvertebrate assemblage structures in temperate zones of North and South America, with those assemblages becoming enveloped by assemblages from the subtropics. Biotic homogenization, more typically associated with other kinds of anthropogenic factors, may also be affected by climate change. Fil: Stenert, Cristina. Universidad de Vale do Rio dos Sinos; Brasil Fil: Pires, Mateus M.. Universidad de Vale do Rio dos Sinos; Brasil Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia San Juan Bosco. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Grech, Marta Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónica. Universidad Nacional de la Patagonia San Juan Bosco. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Maltchik, Leonardo. Universidad de Vale do Rio dos Sinos; Brasil Fil: McLean, Kyle. I.. United States Geological Survey, Northern Prairie Wildlife Research Center; Estados Unidos Fil: Mushet, David.M.. United States Geological Survey, Northern Prairie Wildlife Research Center; Estados Unidos Fil: Batzer, Darold. P.. University of Georgia; Estados Unidos

The large branchiopod crustacean fauna (fairy shrimp, tadpole shrimp and clam shrimp) of the Neotropical Bioregion are incompletely known, with scattered records for many taxa, and many new taxa discovered and described regularly. As an aid to furthering our knowledge of the group in this region, we present an assortment of notes and records on various Neotropical taxa. We present our information in the form of a checklist, listing all reported species, with a review of their known distribution, with 56 new distributional records for 29 taxa. We also include a revised description of Spiralifrons mira based on new material from Brazil, and provide important comments on the Leptestheriidae, reducing Strakrabiidae, Straskrabia, and Brtekia to synonymy. The information presented here will assist in additional studies, surveys, and conservation, as well as help develop a biogeographical understanding of this vast region. Thus, we have compiled these records so that it will be available to other researchers. Future survey efforts will undoubtedly reveal additional records and taxa. Fil: Rogers, D. Christopher. University of Kansas; Estados Unidos Fil: Severo Neto, Francisco. Universidade Federal do Mato Grosso do Sul; Brasil Fil: Volcan, Matheus Vieira. Instituto Pró-Pampa. Laboratorio de Ictiología; Brasil Fil: De los Ríos, Patricio. Universidad Católica de Temuco; Chile Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Ferreira, Aloisio. MUNDI. Biología Integrada Ltda; Brasil Fil: Rabet, Nicolas. Sorbonne University; Francia. Université Pierre et Marie Curie; Francia. Universite de Caen Basse Normandie; Francia. Muséum National d'Histoire Naturelle; Francia. Centre National de la Recherche Scientifique; Francia

Patagonia is by far the largest glacierized area in South America. However, little is known about ecology, functioning and biodiversity of glacier-fed streams facing global warming. We investigated changes in environmental features and macroinvertebrate communities along a longitudinal gradient of glacier influence of two Patagonian systems that differ in glacier cover magnitude and the spatial sequence of lotic and lentic phases. Both glaciers, Torrecillas (~ 5.5 km2, Torrecillas system) and Cónico (~ 0.44 km2, Baggilt system), are retreating. Longitudinal distribution of benthic invertebrates partially fitted to predictions for glacierized temperate systems, with Diamesinae spp. dominating at closest sites to the Cónico, and Orthocladiinae increasing downstream, but patterns were unclear at Torrecillas. Generalized Linear Model identified chlorophyll a and conductivity as having significant effect on richness and density respectively at Torrecillas; detritus biomass and gravel influenced species richness, and boulder percentage and water temperature affected density, at Baggilt. Canonical Correspondence Analyses integrating benthic biota and environmental variables revealed that a higher environmental heterogeneity at Baggilt, related with spatial dimension (unshaded/shaded reaches, wetland reaches), local resources (detritus, bryophytes) and temperature, probably explained the unexpected high richness in benthic assemblages (67 taxa). Environmental conditions imposed by the lake outlet (proglacial) at Torrecillas resulted in a less diverse community (31 taxa). Finally our results suggest that these isolated, small glacier-fed streams typical of the Patagonian landscape appear highly vulnerable to global warming. Endemic elements could disappear at upper segments being replaced by other species common at rhithral environments, which might increase local diversity (alfa diversity) but decrease regional diversity (gamma diversity). From an ecosystem perspective stream functioning can result altered. Glacier retreating or disappearing threatens major ecosystem services for Patagonian inhabitants such as water supply, hydrological regulation, recreation and tourism. Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina Fil: Brand, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina Fil: Di Prinzio, Cecilia Yanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina Fil: Omad, Guillermo Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina Fil: Archangelsky, Miguel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina Fil: Martínez, Oscar. Universidad Nacional de la Patagonia ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina Fil: Kutschker, Adriana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia ; Argentina

The water quality of wetlands is governed not only by natural variability in hydrology and other factors, but also by anthropogenic activities. Patagonia is a vast sparsely-populated in which ponds are a key component of rural and urban landscapes because they provide several ecosystem services such as habitat for wildlife and watering for livestock. Integrating field-based and geospatial data of 109 ponds sampled across the region, we identified spatial trends and assessed the effects of anthropogenic and natural factors in pond water quality. The studied ponds were generally shallow, well oxygenated, with maximum nutrient values reported in sites used for livestock breeding. TN:TP ratio values were lower than 14 in > 90% of the ponds, indicating nitrogen limitation. Water conductivity decreased from de east to the west, meanwhile pH and dissolved oxygen varied associated with the latitude. To assess Patagonian ponds water status we recommend the measure of total suspended solids and total nitrogen in the water, and evaluate the mallín (wetland vegetation) coverage in a 100 m radius from the pond, since those features were significantly influenced by livestock land use. To evaluate the relative importance of natural variability and anthropogenic influences as driving factors of water quality we performed three generalized linear models (GLM) that encompassed the hydrology, hydroperiod and biome (to represent natural influences), and land use (to represent anthropogenic influences) as fixed effects. Our results revealed that at the Patagonian scale, ponds water quality would be strongly dependent on natural gradients. We synthetized spatial patterns of Patagonian pond water quality, and disentangled natural and anthropic factors finding that the dominant environmental influence is rainfall gradient. Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Manzo, Luz Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Grech, Marta Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Macchi, Pablo Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentina. Universidad Nacional de Río Negro. Sede Alto Valle. Instituto de Investigaciones en Paleobiología y Geología; Argentina Fil: Claverie, Alfredo Ñancuche. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel; Argentina Fil: Lagomarsino, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); Argentina Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina

Vital for human consumption, water is a scarce resource, particularly in the arid environments of Patagonia. In this study we analysed local perspectives and the use of different water sources, based on two case studies in rural communities of Mapuche and Creole ancestry inhabiting extra-Andean Patagonia in Chubut, Argentina. Water quality was evaluated using an ethnolimnological, interdisciplinary approach, taking into account local perspectives and scientific contributions. In addition, we analysed appropriation strategies, management and local organoleptic characteristics. The work was based on semi-structured interviews, tours guided by informants, and physicochemical and microbiological analysis of water sources. It was found that 92% of local inhabitants mainly used superficial and subterranean sources of water for consumption, among which stood out: river, streams, springs, wells, and boreholes. Differences were observed between local and scientific perspectives in terms of water quality (chemical and microbiological). Most water sources used by inhabitants presented water of deficient quality for human consumption (61%), whereas locals considered the water to be fresh, delicious, and transparent. Nevertheless, some points of agreement were found in terms of organoleptic characteristics (e.g., odour, colour) and physicochemical parameters in certain water sources. In general, locals do not recognise the deterioration of their water supply, but the importance of organoleptic characteristics in local perception should be highlighted. These aspects speak of a need to promote opportunities for dialogue, and implement effective health measures, taking local perspectives into account. Fil: Morales, Daniela Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Molares, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Ladio, Ana Haydee. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina Fil: Manzo, Pedro. Provincia de Chubut. Dirección Provincial de Área Programática Esquel. Departamento Zonal de Salud Ambiental; Argentina Fil: Alday, Germán Luis. Provincia de Chubut. Dirección Provincial de Área Programática Esquel. Departamento Zonal de Salud Ambiental; Argentina

Anthropogenic and natural changes are threatening pond ecological integrity in Patagonia and tools for bioassessment are required. Macrophytes are good candidates to determine the conservation status of ponds; nevertheless metric selection procedures should be founded on an adequate knowledge of plant ecological responses. We assessed the main environmental constraints driving variation in macrophyte assemblages, and trophic status at 29 ponds located at the continental and insular region Patagonia. We screened 20 potential macrophyte metrics as indicators of pond condition that included origin (exotic, endemic, native), lifeforms (perennial, annual/biannual), functional groups (submersed, emergent, floating-leaved, landforms), and community attributes. A set of 106 taxa were recorded, and richness per site (10.2 species) was unexpectedly high for a cold temperate area, reinforcing the value of isolated ponds as habitat for macrophytes in the Patagonian landscape. Most assemblages were dominated by natives, nevertheless exotics were present at 24 ponds and contributed with high cover (>45%) at 15% of them. Macrophyte assemblages were mainly determined by natural factors over anthropogenic drivers, with temperature, rainfall, conductivity and nutrients explaining most variation in patterns. However, pond eutrophication symptoms (high phosphorous contents and chlorophyll a) were associated with extensive cattle grazing and urbanization. Generalized linear models captured natural variables (temperature, alkalinity) as most powerful explaining richness measures. Nevertheless models also indicated that both richness of emergent and endemics were negatively affected by total phosphorous increases. Land cover factors: grasses/herbaceous, mallín and trees (%) in 100 m buffer around ponds appeared as additional ecological drivers of macrophyte patterns, particularly of submersed (>50%) and native richness (36%). Natural and anthropogenic gradients were overlapped, making it difficult to generalize our conclusions. Further studies are needed to test the performance of the macrophyte metrics selected here, which are a vital tool for the conservation of the most austral ponds in South America. Fil: Manzo, Luz Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Grech, Marta Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Kutschker, Adriana Mabel. Universidad Nacional de la Patagonia "San Juan Bosco"; Argentina Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina

Freshwater biodiversity is showing a global decline in relation to environmental change and there is an urgent need to quantify different facets of biodiversity to assess the conservation value of freshwater ecosystems. Identifying the ecological drivers of arid and semiarid Patagonian waterbodies is a critical requirement for planning action to conserve these still poorly understood habitats. We tested the responses of alpha and beta diversity of invertebrates (presence-absence, abundance, and biomass)to local, landscape, and climatic features, in 45 Patagonian freshwater bodies classified in three groups: isolated ponds, connected ponds, and lotic systems. We first compared the invertebrate community compositions of the different waterbodies. Secondly, using a co-inertia analysis we assessed the relative roles of local, landscape and climatic factors in driving variation in assemblage composition. Finally, we compared different facets of beta diversity and modelled their responses to environmental variables (predictors), by generalized dissimilarity modelling (GDM). Unexpectedly, lotic systems with a total of 109 taxa, were richer than lentic ones, but isolated ponds contributed most to beta diversity and supported more unique and proportionally more endemic species. Alpha and beta diversity were mainly driven by local features and secondly by climatic descriptors. However, these patterns shifted according to different community composition measures. Collectively, our results suggest that isolated ponds have a higher biodiversity value and would be more vulnerable than connected ponds and lotic systems to environmental changes. However, all waterbody types contributed to gamma biodiversity, reinforcing the importance of conserving a diversity of freshwater ecosystems in any landscape and particularly in arid and semiarid Patagonia. Our findings are a first step to resolving and quantifying the amount of changes occurring in Patagonian waterbodies, and are a prerequisite for predicting changes in species distributions in the face of global change. Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Brand, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina

Environmentally sound solutions such as engineered ponds have primarily been established for waste water treatment and flood control in urban areas. However, there is a lack of comprehensive understanding of the factors that influence the aquatic biodiversity of these artificial water bodies, and it has been questioned whether ponds that are designed for water treatment are also able to enhance or support regional biodiversity. The present study (1) examined the water management function of two constructed wetland systems in the urban water cycle: flood prevention ponds (FP) and waste water treatment ponds (WT); (2) analysed their role to enhance local and regional biodiversity (macrophytes and invertebrates); and (3) assessed the functioning of a waste water treatment plant (WTP) in view of regional regulations. As expected, strong differences were found in water quality conditions between FPs and WTs, mostly in terms of nutrients, conductivity, suspended solids and oxygen levels. FPs created optimal environments harboring several species of macrophytes and supporting diverse invertebrate assemblages, comparable to those recorded at natural ponds. On the contrary, WTs sustained three times less taxa, with Psychoda sp. and Chironomus sp., (dipterans indicators of poor ecological conditions) dominating the assemblage. The waste water treatment plant was partially successful with regards to domestic effluent processing. Nutrient values for treated effluents exceeded the permissible standards for receiving surface waters in the region. Constructed ponds offer an opportunity for managers and environmental regulators to conserve and enhance aquatic biodiversity in ecologically poor environments. In addition to other ecosystem services (sociocultural), FPs also promoted biotic biodiversity. WTs functioned as nutrient sinks rather than as biodiversity spots, but their biodiversity and functioning could be enhanced through proper design and management. Some feasible solutions to improve WTP functioning are itemized and discussed. Fil: Manzo, Luz Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Horak, Cristina Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Kutschker, Adriana Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagóica. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Centro de Investigación Esquel de Montaña y Estepa Patagónica; Argentina

On May 2nd of 2008 the Chaiten Volcano (Chile, 42°50′S and 72°39′W) erupted explosively producing a strong emission of volcanic ash. As a result of this eruption wide areas on the Argentinean side became covered by ashes. In order to investigate the effects of ashfall on environmental features, water quality and macroinvertebrate communities we conducted a study on 10 rivers affected by ash deposition in their hydrographic basins. Sites were visited seasonally (June 2008–March 2010) and results were compared with data obtained from previous research projects. Measures of pH, conductivity, oxygen content, main nutrients, and total suspended solids (TSS) were taken. Macroinvertebrate samples were obtained from riffles and pools. Community attributes were measured and metrics were calculated. A strong and significant increase in TSS values at most sites was recorded and although the peak diminished rapidly during the following months, resuspension and remobilization of ash continue even 20 months after. No significant changes in pH, conductivity and nutrients, comparing with data previous to the ashfall, were detected. Most rivers showed a strong diminution on macroinvertebrate density and richness, being small rivers more severely affected than the big ones. Correspondence analysis based on abundance data allows distinguishing preeruption from posteruption dates at five rivers. Density data and species richness showed low values in March of 2010, indicating that the community was not completely recovered at some sites. At least 25 taxa resulted significantly and negatively affected. Increased mortality could be related to several factors such as habitat deterioration, food quality diminution, interference with breathing mechanisms and with other physiological and morphological characteristics. Specific-taxa responses on the recolonization process were related to dispersal mechanisms and specific strategies.

Substrate, flow type, nutrients, aquatic vegetation, organic matter, and caddisfly community structure were studied at two low order streams (Glyn and Nant y Fall) subjected to pastoral use in the Patagonian mountains. At both sites, we examined the effect of habitat type (boulder-pebble with and without filamentous algae, cobble-pebble, gravel-sand, leaf-pack, the submerged macrophytes Myriophyllum quitense and Isoetes savatieri) and season (high and low water period) on caddisfly assemblages. Benthic particulate organic matter (BPOM) ranged between 4.6 and 472 g m–2, all allochtonous detrital fractions were significantly higher at leaf-packs at Glyn, whereas M. quitense habitats supported more BPOM and macrophytes biomass at Nant y Fall. As expected, boulder-pebble sustained higher Trichoptera richness than M. quitense and gravel-sand, moreover all habitats showed higher density than M. quitense at Nant y Fall. According to our results at least nine caddisfly species exhibited some habitat preference with boulder-pebble and cobble-pebble the most selected habitat. These particular habitats sustained more than 68% of the total caddisfly species. Multidimensional scaling ordination highlighted differences in composition per habitat for both sites showing a clear distinction among depositional and erosional habitats. Substrate, flow type, detritus biomass were important predictors defining assemblages. Based upon our findings, those anthropogenic actions or stressors that change hydraulic as well substrate attributes in mountain streams such as stock trampling, dredging, clearing of riparian areas, will reduce caddisfly richness. These results are relevant for outline management and conservation biomonitoring and schemes in headwater Patagonian streams as well as other similar environments worldwide (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We examined the life history, annual production, diet, habitat preferences and competition of two species of stoneflies Notoperla fasciata and N. magnaspina in a Patagonian mountain headwater stream. Benthic samples and adult collections were taken monthly from July 2004 to June 2005. A habitat selection study was performed concurrently during high and low water periods in five substrate types. Although both species showed long life cycles (N. fasciata: 20 months and N. magnaspina: 3 years) their life histories and temporal dynamics were different. Growth was rapid during summer and early autumn as a result of warmer temperatures but N. magnaspina had a shorter emergence period (November to January) than N. fasciata (January to April). N. fasciata was the dominant Notoperla species with a mean annual density 6 times higher and secondary production 4.5 higher than that of N magnaspina. While boulders in riffles and pools, and leaf-pack habitats supported significantly more individuals of N. magnaspina in the low water period (ANOVA, p 0.26). N. fasciata dominated in the high water period and N. magnaspina during the low water period. Analysis of gut contents revealed that both species were herbivorous grazers, and consumed the same food types. The interspecific overlap in density, biomass and annual production among habitat types was high in the low water period (PS> 0.5). However, N. fasciata were smaller than N. magnaspina. The existence of different life history strategies and the temporal shift of main generations and density peaks were critical to allow species coexistence and to reduce competition.

Temporary seasonal ponds are ubiquitous and numerous but overlooked habitats found throughout the world’s temperate biomes. They include the natural ponds of grassland and woodland such as prairie potholes and pampas mallines but also anthropogenic subsidence ponds and depressions in intensively managed landscapes. These ponds are hotspots for invertebrates which benefit from the absence of fish, resulting in both high species richness, e.g. beetles, and characteristic rare and endemic taxa, e.g. many larger Crustacea. The invertebrates’ ecology is dominated by hydrology and the interplay of dispersal and species’ interactions, primarily predation. Individual species vary greatly in their traits and behaviours, resulting in complex metacommunity dynamics.

Ponds are worldwide recognized as biodiversity hotspots, nevertheless in Patagonia are still needed studies that reveal the composition and the status of their communities. This paper analyses the temporal patterns of aquatic invertebrates and assesses the environmental factors that best predict the variation in community structure at three small intermittent ponds, subjected to ranching practices (summer stocking) in the Patagonia steppe. Variables identified as important in structuring community assemblages were related to environmental conditions (rainfall and water temperature), chemical features (conductivity and pH) and biotic factors (macrophyte coverage). During the connected phase only a small number of invertebrate species were present, in contrast to the 11 taxa that were frequent and abundant during isolated period (Eucyclops chilensis, Hyalella curvispina, and Rhionaeschna sp. were the dominant ones). In this sequence the submersed Myriophyllum quitense and Lilaeopsis macloviana played a crucial role offering habitat and food resources. The present study provides valuable information that can contribute to minimize the environmental damage and to develop strategies for the conservation of Patagonian wetlands. Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónicas; Argentina Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónicas; Argentina

Livestock grazing can compromise the biotic integrity and health of wetlands, especially in remotes areas like Patagonia, which provide habitat for several endemic terrestrial and aquatic species. Understanding the effects of these land use practices on invertebrate communities can help prevent the deterioration of wetlands and provide insights for restoration. In this contribution, we assessed the responses of 36 metrics based on the structural and functional attributes of invertebrates (130 taxa) at 30 Patagonian wetlands that were subject to Different levels of livestock grazing intensity. These levels were categorized as low, medium and high based on eight features (livestock stock densities plus seven wetland measurements). Significant changes in environmental features were detected across the gradient of wetlands, mainly related to pH, conductivity, and nutrient values. Regardless of rainfall gradient, symptoms of eutrophication were remarkable at some highly disturbed sites. Seven invertebrate metrics consistently and accurately responded to livestock grazing on wetlands. All of them were negatively related to increased levels of grazing disturbance,with the number of insect families appearing as the most robust measure. Amultivariate approach (RDA) revealed that invertebrate metrics were significantly affected by environmental variables related to water quality: in particular, pH, conductivity, dissolved oxygen, nutrient concentrations, and the richness and coverage of aquatic plants. Our results suggest that the seven aforementioned metrics could be used to assess ecological quality in the arid and semi-arid wetlands of Patagonia, helping to ensure the creation ofprotected areas and their associated ecological services Fil: Miserendino, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónicas; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Centro de Investigación Esquel de Montaña y Estepa Patagónicas; Argentina

Aquatic macrophyte assemblages and environmental features were assessed in 30 wetlands from North- west Patagonia subjected to different intensity of grazing pressure. Species richness was surveyed in wetlands from three biozones of the Patagonia Ecoregion: Andean-Humid, Sub-Andean Sub-Humid and Extra-Andean Occidental. A total of 50 species of macrophytes were recorded, with the Cyperaceae, Jun- caceae, Poaceae and Ranunculaceae the best represented groups. Canonical Correspondence Analysis (CCA) reflected the distribution of species along a gradient of disturbance (CCA1: salinity and ammo- nia). There was also a correspondence among community composition and intensity of grazing pressure at isolated wetlands, with total species richness, richness of natives and aquatic plant coverage significantly decreasing towards most disturbed sites. Only the species Distichlis spicata, Xanthium spicatum and Eleocharis melomphala appeared as indicators of wetland deterioration associated with degraded sites, subjected to strong erosion processes which increase the natural soil salinity. The submersed Lilaeopsis macloviana was the most tolerant species being recorded over a wide range of environments and inten- sity of land uses. Variables related to wetland size and connectivity (CCA2: depth, length, elevation and dissolved oxygen) displayed higher explanatory power on community assemblages, and subsequently macrophyte life-forms were clearly distinguished across this gradient. Most of species recorded in this work were native, however the proportion of exotics reached 25% in areas with intermediate and high grazing intensity. Although we were not able to clearly separate natural from grazing effects this study provides a first look at natural and anthropogenic controls of macrophytes in Patagonian wetlands. Fil: Kutschker, Adriana Mabel. Universidad Nacional de la Patagonia; Argentina Fil: Epele, Luis Beltran. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Departamento de Biología. Laboratorio de Investigaciones en Ecología y Sistemática Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Miserendino, Maria Laura. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales - Sede Esquel. Departamento de Biología. Laboratorio de Investigaciones en Ecología y Sistemática Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Lynceus mallinensis, a new species of laevicaudatan clam shrimp is described from a single temporary pool in Chubut province, Patagonia, Argentina. The form of the male rostrum necessitates a reevaluation of rostral characters for the genus. This species differs from L. rotundirostris, the only known Lynceus from Patagonia, by the absence of a distinct umbo. L. mallinensis is the fourth species of this genus and the fifth laevicaudatan to be reported from South America. The systematical position of the Laevicaudata is discussed in the Introduction. Lynceus mallinensis, una nueva especie de Laevicaudata, es descrita a partir de material recolectado en un mallín temporal en la provincia de Chubut, Patagonia, Argentina. Esta especie difiere de L. rotundirostris, la única especie descrita en Patagonia, por la ausencia de umbo. L. mallinensis es la cuarta especie del género y el quinto Laevicaudata registrado en América del Sur. Fil: Pessacq, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia; Argentina Fil: Epele, Luis Beltran. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia; Argentina Fil: Rogers, D. Christopher. University of Kansas; Estados Unidos

Life history descriptors of mayfly species are increasingly used in ecological assessment studies as indicator of environmental stress and also to evaluate the potential effects of climate change. We investigated the life history, annual production and competition of two congeneric mayflies: Andesiops torrens and Andesiops peruvianus in a Patagonian mountain headwater stream (La Hoya). From July 2004 to June 2005 a monthly sampling was conducted at riffle areas using a Surber net. Mean density of A. torrens ranged from 26 to 1080 ind m −2 whereas that of A. peruvianus ranged from 7 to 629 ind m −2 . The annual production and P / B ratios of A. torrens (0.18 g m −2 , 3.90) and A. peruvianus (0.11 g m −2 , 3.35) at La Hoya stream were low, but within the expected values for cold water environments at high elevations. The two species had a similar larval life history with small larvae predominating in late summer and early autumn, middle size larvae being represented throughout winter, and mature larvae and emergence occurring in summer. As a result A. torrens and A. peruvianus showed moderately synchronized univoltine life cycles. The temporal interspecific overlap on both density and biomass was very low. This suggests that these two species of grazers reduce the competition for resources by having a marked temporal segregation.