Ecología Diversidad estacional de arañas en una reserva natural delEspinal en Corrientes, Argentina nadal@gmail.com* ceciliaachitte@hotmail.com, ivo.zanone@gmail.com, pamelagonzalez052@ gmail.com, gilbertoa@exa.unne.edu.ar *Autor para correspondencia. RESUMENEvaluar la diversidad de arañas es necesario para la conservación de la naturaleza ya que cumplen un rol importante en los ecosistemas como reguladoras de las poblaciones de insectos y son buenas indicadoras de calidad ambiental. La reserva contemplada en este estudio es singular dentro de la llanura del Espinal debido a sus afloramientos rocosos, que contienen una gran diversidad de especies, varias de ellas de carácter endémico. Los objetivos de este trabajo fueron crear un inventario, describir la diversidad taxonómica y funcional del orden Araneae en bosques y pastizales en función de las estaciones climáticas. Los muestreos se realizaron mediante tamizado de hojarasca, golpeteo de follaje, aspirado de pastizal y captura directa nocturna. Para cada ambiente se calcularon índices de diversidad alfa y beta temporal y se probó el modelo de distribución de abundancia. Se identificaron 224 especies/ morfoespecies. Theridiidae fue la familia con mayor riqueza y el gremio Constructoras de Telas Orbiculares el más abundante. Los índices de diversidad, dominancia y equidad mostraron diferencias significativas entre las estaciones cálidas y frías para bosques y pastizales, la distribución de abundancia de las especies se ajustó al modelo de distribución log-normal y la similitud de especies entre estaciones no superó el 41 %. Los resultados de este estudio aportan datos preliminares sobre los patrones estacionales de la comunidad de Araneae. Se reportan nuevas especies de arañas para Argentina, muchas ellas con registros escasos y aislados en Sudamérica, así como especies de importancia ecológica.Palabras Clave. Arañas, comunidad, gremios, reserva privada, estaciones climáticas. ABSTRACTAssessing the spider's diversity is necessary for the conservation of nature since they play an important role in ecosystems as regulators of insect populations and are good indicators of environmental quality. The reserve contemplated in this study is unique within the Espinal's plain due to its rocky outcrops, which contain great species diversity, several of them endemic. The objectives of this work were to create an inventory, describe the taxonomic and functional diversity of the Araneae order in the reserve's forests and grasslands according to the climatic seasons. The samplings were carried out by leaf litter sieving, foliage beating, grassland aspirate and nocturnal direct capture. For each environment, alpha and beta diversity indices were calculated and the abundance distribution model was tested. In total 224 species/morphospecies were identified. Theridiidae was the richest family and the Orbicular Webs Builders guild was the most abundant. Diversity, dominance and equitability indices showed significant differences between warm and cold seasons for forests and grass...

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Anexo 1. Familias y especies/morfoespecies de arañas recolectadas en bosques y pastizales de la Reserva Natural Privada Paraje Tres Cerros, Corrientes, Argentina. Anexo 2. Composición, riqueza y abundancia de los gremios de arañas en bosques y pastizales de la Reserva Natural Privada Paraje Tres Cerros, Corrientes, Argentina.*Documento principal: https://doi.org/10.15446/caldasia.v40n1.67362

Background The exclusion of tourist species from samples is important to avoid bias in community analyses. However, in practice, this is a very difficult task. The commonly used methods by researchers, when the habitat of the species is not known, have several shortcomings: first, they exclude not only pseudo-rare species but also genuinely rare species; second, the results obtained with those methods depend on the abundance of the sampling; and third, they follow very subjective rules. The aims of this study were: (i) to propose a methodology to detect and exclude habitat-tourist species from the database used to carry out analyses in community ecology studies, (ii) to evaluate how the presence of habitat-tourist species affects the richness estimates, and (iii) to assess the effect of including juvenile spiders in the detection of tourist species and the effect of removing them from the richness estimates. Results When the adult + juvenile dataset was considered, twenty-one habitat-tourist species were detected: 8 in forest foliage, 11 in forest leaf litter, and 2 in grassland. When habitat-tourist species were considered with this dataset, richness overestimation was significant in foliage and in leaf litter, and the final slopes of the richness estimation curves were significantly steeper in leaf litter. When only the adult dataset was considered, eight habitat-tourist species were detected: 3 in forest foliage, 4 in forest leaf litter, and just one in grassland. The inclusion of habitat-tourist species in this dataset showed an overestimation of richness, but this was not significant. Conclusions The proposed methodology contributes to solving the problem of tourist species, which was recognized as one of the great problems in biodiversity studies. This study showed that common estimators overestimate species richness when habitat-tourist species are included, leading to erroneous conclusions. Besides, this research showed that the inclusion of juveniles (e.g. spiders) could improve the analysis outputs because it allowed the detection of more habitat-tourist species.

Gran número de especies nuevas de arañas están a la espera de ser descritas, y en muchos casos el conocimiento es incompleto porque se conoce un solo sexo. En esta contribución, la hembra de la araña saltadora Lyssomanes miniaseus es descrita y por primera vez se ilustra su morfología. La hembra se distingue por tener las espermatecas esféricas, ligeramente ovales, una posición atrasada de los orificios copulatorios, y pelos blancos esparcidos ventralmente sobre los fémures I y II; podría ser este último carácter una característica compartida por ambos sexos potencialmente única a esta especie. Adicionalmente, se presenta aquí un nuevo registro más al sur y una nueva ilustración de la especie poco conocida L. belgranoi.

A�������. The spiders of the Salticidae family can be valuable indicators of various environmental conditions because they are distributed over almost all continents and are found in a wide variety of habitats and in all climatic seasons. It was assessed if species of Salticidae function as indicators of the conservation status of habitats and if the use of adult+juvenile or adult-only data yields different results. Spiders were collected in two natural parks and two semi-natural areas located between both parks in an area of Eastern Chaco, Argentina. The samples were taken from three types of habitats: foliage, leaf li�er and grassland. The analysis of indicator species was conducted with the indicator value index (IndVal). A high IndVal value for a species in a habitat (e.g., semi-natural grassland) indicates that it is specific (relatively abundant) and faithful (evenly distributed) to that habitat. The species that presented IndVal values >0.45 and >0.70 were classified as detectors and indicators, respectively. Indicator species are highly characteristic of a group (exclusive or nearly exclusive), while detector species prefer a group, but are not exclusive to it. Philira micans was found to be a detector for the semi-natural foliage; Semiopyla viperina, for the natural leaf li�er and Maeota dorsalis, for the natural grassland. The use of the adult+juvenile dataset provided more information about the number of IndVal-significant species; the three detector species mentioned were detected exclusively from this dataset. This study demonstrates that Salticidae spiders in the studied area are sensitive to the conservation status of the analyzed habitats as detector species were recorded. Besides, this study demonstrates that the adult+juvenile dataset improves the detection of species sensitive to changes.

Wedoquella apnnea sp. nov. and W. karadya sp. nov., two new species of the jumping spider subtribe Freyina are described and illustrated from specimens recently collected in Misiones and Chaco provinces, Northeastern Argentina. The new species are placed into a new group of Wedoquella because, although in body morphology they resemble the Phiale gratiosa group, the genital structures of both sexes more closely resemble those of Wedoquella, and a preliminary analysis based on mitochondrial COI sequences places this new group as sister to Wedoquella rather than to Phiale. Both new species are similar, but can be distinguished mainly by differences in the retrolateral tibial apophysis of the male palp. Females have a slight intraspecific color variation.

In this work, Pseudofluda palachiyaxa n. sp. found in Chaco, Argentina, is described and illustrated. In addition, new drawings of the previously described species of the genus Pseudofluda, distribution maps, and a habitat photograph are included.