This study examined arthropod community patterns over an altitudinal ecoregional zonation that extended through three ecoregions (Yungas, Monte de Sierras y Bolsones, and Puna) and two ecotones (Yungas-Monte and Prepuna) of Northwestern Argentina (altitudinal range of 2,500 m), and evaluated the abiotic and biotic factors and the geographical distance that could influence them. Pitfall trap and suction samples were taken seasonally in 15 sampling sites (1,500–4,000 m a.s.l) during one year. In addition to climatic variables, several soil and vegetation variables were measured in the field. Values obtained for species richness between ecoregions and ecotones and by sampling sites were compared statistically and by interpolation–extrapolation analysis based on individuals at the same sample coverage level. Effects of predictor variables and the similarity of arthropods were shown using non-metric multidimensional scaling, and the resulting groups were evaluated using a multi-response permutation procedure. Polynomial regression was used to evaluate the relationship between altitude with total species richness and those of hyperdiverse/abundant higher taxa and the latter taxa with each predictor variable. The species richness pattern displayed a decrease in species diversity as the elevation increased at the bottom wet part (Yungas) of our altitudinal zonation until the Monte, and a unimodal pattern of diversity in the top dry part (Monte, Puna). Each ecoregion and ecotonal zone evidenced a particular species richness and assemblage of arthropods, but the latter ones displayed a high percentage of species shared with the adjacent ecoregions. The arthropod elevational pattern and the changes of the assemblages were explained by the environmental gradient (especially the climate) in addition to a geographic gradient (the distance of decay of similarity), demonstrating that the species turnover is important to explain the beta diversity along the elevational gradient. This suggests that patterns of diversity and distribution of arthropods are regulated by the dissimilarity of ecoregional environments that establish a wide range of geographic and environmental barriers, coupled with a limitation of species dispersal. Therefore, the arthropods of higher taxa respond differently to the altitudinal ecoregional zonation.

RESUMEN Se conoce poco sobre la biología y la ecología de la especie mirmecófaga Leprolochus birabeni Mello-Leitão, 1942 (Zodariidae), el único representante de este género en la Argentina. Esta especie es típica de ambientes áridos del norte del país, y su estudio en el Chaco Seco es relevante, por ser una ecorregión altamente perturbada con uno de los pocos bosques subtropicales secos del mundo. El objetivo de este trabajo es estudiar la demografía de la especie teniendo en cuenta su variación estacional en ambientes nativos, y sí la ganadería y la agricultura, dos de las actividades antropogénicas más comunes de la ecorregión Chaco Seco en la provincia de Salta (Argentina) producen cambios en sus poblaciones. Se consideraron tres tipos de ambientes: nativo (NA); afectados por el ganado vacuno y caprino (NP); y afectados por la agricultura (NC). Este último correspondió a parches de vegetación nativa en medio de una matriz agrícola. En cada tipo de ambiente se consideraron tres sitios de muestreo donde se realizaron muestreos estacionales utilizando trampas de caída durante el otoño, invierno y primavera de 2006 y el verano de 2007. Se recolectaron 549 ejemplares de L. birabeni , siendo la mayoría juveniles con el 64,12% de la abundancia total, seguidos por machos (26,41%) y hembras (9,47%). A nivel de paisaje, la primavera presentó el mayor número de individuos, llegando al 44,99% de la abundancia total; mientras que el otoño mostró el porcentaje más bajo (7,83%). El incremento de los juveniles durante el invierno podría indicar una adaptación de los estadios de desarrollo a las condiciones ambientales. El mismo patrón se observó en ambientes NA y NC, pero no en los NP. Estos últimos mostraron una disminución en la abundancia de adultos a lo largo del año; mientras que las poblaciones NC mostraron un incremento en la abundancia de los machos durante la primavera, con una fuerte reducción de las hembras y los juveniles durante todo el año. La abundancia de L. birabeni en ambientes NA fue mayor (41,06% de la abundancia total), siendo los valores mínimos registrados en NC (24,67%). Las dos actividades antropogénicas más comunes que afectan al Chaco Seco de la provincia de Salta modifican tanto los cambios estacionales como la representación de las diferentes etapas de desarrollo y sexos de las poblaciones nativas de L. birabeni , siendo la modificación de los ambientes nativos por la agricultura, el factor más perjudicial.

Argentine tardigrades are relatively unknown and, in many cases, unstudied; in the province of Salta in northwestern Argentina the lone record of tardigrade dates to the 1980s. Here, we evaluate and compare tardigrade diversity in natural habitats (N), urban environments (U) and rural communities (R) of Yungas. This work seeks to verify the existence of a reduction in tardigrade diversity outside their native habitats and if there is a biotic homogenization in the urban communities. Tardigrade community assemblages were compared between habitats using non-metric multidimensional scaling and a multi-response permutation procedure. Beta diversity was analysed in its component parts, species turnover and nesting, using a modified Raup-Crick test. Gamma diversity was divided into alpha and several beta levels. In total, 2080 eutardigrade and heterotardigrade specimens were registered and showed differences in tardigrade assemblages between habitats; the most diverse habitat was R. The beta diversity partition showed a nesting pattern in the U communities, highlighting faunal homogenization, while species turnover was key in the R and N communities. There was species loss from N to U communities, most markedly between R and U; various forces (both stochastic and deterministic) influence the structure of these communities.

RESÚMEN Este trabajo se realizó bajo la hipótesis de que existe una pérdida creciente de diversidad en las comunidades de tardígrados, desde las áreas rurales hacia las urbanas, incrementando la homogenización de sus comunidades producto de la urbanización. Para la ciudad de Salta, se tomaron muestras en áreas con tránsito vehicular alto y muestras en áreas rurales circundantes. Se identificaron en total ocho especies/morfoespecies. El inventario tuvo una completitud mayor al 94%. La comunidad rural fue más diversa y estructuralmente más uniforme que la comunidad urbana. Macrobiotus hufelandi Schultze, 1834 resultó especie indicadora y Milnesium sp. como detectora para el hábitat urbano, mientras que Paramacrobiotus areolatus Murray, 1907 resultó indicadora para el hábitat rural.

Abstract:We report new records of pholcid species for northern Argentina.

Ecología Diversidad taxonómica y funcional de arañas (Araneae) epigeas en bosques nativos de las Yungas (Salta, Argentina)Taxonomic and functional diversity of epigeal spiders (Araneae) in native forest of the Yungas (Salta, Argentina) (UNSa). Av. Bolivia 5150. Salta, Argentina. torres.vicman@gmail.com, andyximena@gmail.com José antonio corronca Consejo Nacional de Investigaciones Científicas y Técnicas, UNSa, IEBI. Av. Bolivia 5150. Salta, Argentina. jcorronca@gmail.com Victor ManuEl torrEs, andrEa XiMEna gonzálEz-rEyEs Instituto para el Estudio de la Biodiversidad de Invertebrados (IEBI), Universidad Nacional de Salta RESUMENEl estudio de la araneofauna en las Yungas argentinas es escaso. Sin embargo, es relevante debido a la alta diversidad ambiental y biológica que posee esta ecorregión, principalmente en los sistemas forestales amenazados por el avance de la frontera agropecuaria. El objetivo de este trabajo es comparar la diversidad y la composición de los ensambles de arañas epigeas en la Selva Pedemontana (SP), Selva Montana (SM) y Bosque Montano (BM) de las Yungas de la provincia de Salta. Se tomaron muestras mediante trampas de caída durante el otoño, la primavera 2006 y el verano 2007 en tres sitios de la SP, cinco en la SM, y tres en el BM. Se recolectaron 643 arañas pertenecientes a 75 especies/morfoespecies. Los ensambles de SP reportaron la mayor riqueza de especies sumado a una composición de especies muy disímil en relación con las de SM y BM. Las tejedoras espaciales, otras cazadoras y cazadoras de suelo representaron más del 95 % de la abundancia en cada comunidad. Ellas mostraron patrones semejantes de abundancia en la SM y BM, mientras que en la SP las tejedoras espaciales redujeron marcadamente su abundancia. El cambio en la configuración del paisaje debido al uso del suelo es la principal fuerza que estaría estructurando los ensambles locales de la SP. Este estudio constituye el primero en analizar la diversidad de arañas epigeas y sus gremios en las Yungas del norte argentino siendo un punto de partida para futuros monitoreos de biodiversidad en la región.Palabras clave. Araneofauna, ecoregión, ensambles de especies, gremios, uso del suelo. ABSTRACTThe study of the arachnofauna in the argentinean Yungas is scarce. However, it is relevant due to the high environmental and biological diversity, mainly in the forest systems threatened by the advance of the agricultural frontier. The aim of this work is to compare the diversity and composition of epigeal spider assemblages in the Piedmont Forest (SP), Mountain Jungle (SM) and Mountain Forest (BM) of the Yungas in the province of Salta. Three sites of the SP and BM, and five of the SM were considered. Sampling was carried out during autumn, spring (2006) and summer (2007) with pitfall traps. A total of 643 spiders of 75 species/morphospecies were collected. The SP sites showed the highest species richness and species composition very dissimilar compared to the SM and BM. The space web weavers, other hunters and ground hunters accounted...

The increased degradation of natural habitats has strengthened the need to know and assess biodiversity patterns. Particularly, the study of the araneofauna in the North of Argentina is scarce in ecoregions with priority interests of conservation. Generally, spiders are used as indicators to compare biodiversity patterns, and here we tested whether the spider family-level can act as a substitute of the species-level in biodiversity rapid assessments. For this, we analyzed the alpha and beta diversity of the epigeal spider communities in three separate sites of different ecoregions of Salta province (Chaco Serrano, Monte de Sierras and Bolsones, and Puna), during the fall, winter, spring and summer of 2005 -2007. In each site, 10 pitfall traps, located along a linear transect and 10 meters apart, were placed for seven days per season of continuous activity. Samples were obtained, taken to the laboratory and identified. A total of 886 spiders were collected from 100 species/morphospecies of 19 families. The completeness of the inventory obtained for each ecoregion surpassed 70 %. The Chaco ecoregion (S = 56, N = 495) reported the highest species richness and abundance compared to Monte (S = 44, N = 262) and Puna (S = 23, N = 129). Alpha and beta diversity showed that ecoregional spider communities were different, sharing between them very few species (0.7 %). The Chaco reported a high dissimilarity of its assemblage with respect to the other ecoregions. The colder seasons (autumn and winter) proved to be important in assessing the diversity of spiders in these ecoregions, contributing to regional diversity in conjunction with the diversity of warm seasons (spring and summer). Four guilds were reported (ground hunters, specialists, other hunters and ambush hunters), but the latter was absent in Monte, and the specialists dominated in Chaco. Zodariidae was dominant in Chaco Serrano, where Leprolochus birabeni is an indicator of native environments. On the other hand, Lycosidae, Philodromidae, Anyphaenidae and Oonopidae were important for Monte and Puna. This way, the use of pitfall traps in all seasons of the year, and the recognition of spider families for epigeal fauna, was very useful for biodiversity rapid assessments in this area. Like the species-level, the taxonomic family-level evidenced changes in alpha and beta diversity. This allowed the inclusion of this taxonomic group for future biodiversity monitoring studies for conservation plans in these ecoregions.

Studies under constant temperatures are the most common to estimate the Postmortem Interval (PMI). It is imperative that forensic sciences have data from studies carried out in the field. Therefore, this work aims to: (1) evaluate the parameters (weight, length, development time) associated with the life cycles of Lucilia ochricornis (Wiedemann) (Diptera: Calliphoridae) and Lucilia purpurascens (Walker) under experimental conditions in the field considering fluctuating temperatures, and (2) compare these results with those known and published by the same authors for cultures realized in the laboratory under constant temperatures; which will permit us to contrast the most widely used existing methodologies for forensic application in estimating the minimum postmortem interval (PMImin). For each season of the year, cultures of both species were made in the field, collecting information on temperature, humidity, and photoperiod to perform laboratory cultures, later comparing: development time, length, weight, and Accumulated Degree-Hours (ADH) in both types of cultures. Methods for estimating the PMI were obtained and validated with the information of the cultures grown in the field. The two types of cultures showed differences between each other for both species. The forensic use methods to estimate PMI were enhanced and their precision increased when maximum larval length data were used, and it was also concluded that feeding larval stages are the most accurate to be used in making estimates because the larva is growing. The estimation of the PMI through the use of necrophagous flies development remains reliable for obtaining the PMImin.