Descripción del macho de Stenoterommata uruguai (Araneae: Mygalomorphae: Nemesiidae) del noreste de Argentina, con notas sobre su historia natural

The male of Stenoterommata uruguai Goloboff, 1995 is described and illustrated for the first time. A photograph of a female spermathecae collected at the same locality is also presented to confirm the identification, as well as data on the natural history of this species.Se describe e ilustra por primera vez el macho de Stenoterommata uruguaiGoloboff, 1995. También se presenta una fotografía de la espermateca de una hembra recolectada en la misma localidad para confirmar la identificación y se registran datos sobre la historia natural de esta especie.Fil: Ferretti, Nelson Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Pompozzi, Gabriel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; Argentin

Feeding frequency, prey acceptance, and natural diet of the mygalomorph spider acanthogonatus centralis goloboff 1995 (Araneae: Nemesiidae)

The family Nemesiidae is the second most diverse family of Mygalomorphae spiders. Acanthogonatus centralis (Nemesiidae) is commonly found in hilly areas of central Argentina. These spiders are considered generalists due to their basal position in the phylogeny, but little is known about the trophic ecology of the species. Therefore, the objectives of this study were to study some of the species’ predatory traits, such as feeding frequency and prey acceptance, and to assess its natural diet. In addition, two parameters - attack latency and consumption time - were measured for each accepted prey. We found that A. centralis feeds every two days and accepts almost all prey offered. The most accepted prey items were beetle larvae and termites. In fact, termites were attacked faster than any other prey, suggesting they are a suitable prey for these spiders. In regard to the species’ natural diet, we found remains of seven prey items, ants and beetles being the most frequent. In this study, we found that Acanthogonatus centralis is polyphagous since it accepts different kinds of prey.Fil: Pompozzi, Gabriel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Copperi, Maria Sofia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; Argentin

The Invasive Spider Badumna longinqua (L. Koch, 1867) (Araneae: Desidae) in Argentina: New Distributional Records, with Notes on its Expansion and Establishment

Badumna longinqua (L. Koch 1867) is a medium-sized spider native from Australia. Due to its synanthropic habitat, this spider expanded their range distribution, reaching Germany, Japan, New Zealand, Uruguay and USA. We found specimens of this species in different localities from Buenos Aires Province, Argentina. Therefore, we report the first records of B. longinqua to Argentina, and discuss aspects of its distribution.Fil: Pompozzi, Gabriel Alejandro. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados Ii; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Peralta, Luciano. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología. Laboratorio de Artrópodos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Simó, Miguel. Universidad de la República. Facultad de Ciencias; Urugua

On the ecology of the cursorial spider Odo bruchi (Araneae: Zoridae) in a grassland natural reserve from central Argentina

The “Ernesto Tornquist” Provincial Park (ETPP) is located inside the Ventania system (Argentina) and was created to protect one of the last relicts of pampean grasslands. Even though many studies have looked at the vertebrate faunal diversity, biology, and conservation in this Park, few studies have been dedicated to arthropods. Among these, spiders have been used as ecological indicators to evaluate nature conservation status, nevertheless, basic information on their distribution and ecology is necessary for their use as indicator taxa in this region. Thus the goal of this study was to present the phenology and demography of the spider Odo bruchi, a cursorial spider present in the ETPP. For this, spiders were sampled bimonthly using pitfall traps between September 2009-2010 (first year), and March 2011-2012 (second year). A total of 10 traps were placed every 10m along a transect of 100m parallel to the longest axis of a grassland slope with native vegetation. Traps were filled with 1 500mL of ethylene glycol, that were examined and refilled every 60 day period. We collected a total of 799 specimens in two years. Juveniles were the most abundant reaching 47.8% of the total, while males corresponded to 27.8% and females 24.4%. We found significant differences in the mean abundance of O. bruchi: the abundance during spring-summer (Nov-Dec-Jan-Feb) was significantly higher than the other periods of the two years period. Moreover, we found an even abundance distribution throughout the year in the entire study. This work represents one of the first contributions to the ecology of this spider family in the area. Also, our results comprise relevant information to encourage future studies on this spider species as a bio-indicator of the conservation status of pampean grasslands.Fil: Pompozzi, Gabriel Alejandro. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados II; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Copperi, Maria Sofia. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados II; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Schwerdt, Leonela Vanesa. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados II; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ferretti, Nelson Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentin

Species conservation profile of the rare and endemic trapdoor spider Calathotarsus simoni (Araneae, Migidae) from Central Argentina

Background: Calathotarsus simoni Schiapelli & Gerschman 1975 is the only species of Migidae in Argentina. It is a rare and endemic spider only found in relict grassland of mountain systems in the province of Buenos Aires. This species is a habitat specialist spider occupying specific areas with certain microclimatic conditions on hilly and rocky grassland areas at about 500-1500 meters above sea level. New information: The observed extent of occurrence (EOO) is 7207 km2 and the area of occupancy (AOO) is 16 km2. Two locations are identified based on the threat event related to the invasion of the species habitat by alien woody plants. In addition, intensive cattle production and agriculture also constitute relevant threats to the species.Centro de Estudios Parasitológicos y de VectoresUniversity Of HelsinskiFinnish Museum of Natural Histor

Species conservation profile of the rare and endemic trapdoor spider Calathotarsus simoni (Araneae, Migidae) from Central Argentina

Background: Calathotarsus simoni Schiapelli & Gerschman 1975 is the only species of Migidae in Argentina. It is a rare and endemic spider only found in relict grassland of mountain systems in the province of Buenos Aires. This species is a habitat specialist spider occupying specific areas with certain microclimatic conditions on hilly and rocky grassland areas at about 500-1500 meters above sea level. New information: The observed extent of occurrence (EOO) is 7207 km2 and the area of occupancy (AOO) is 16 km2. Two locations are identified based on the threat event related to the invasion of the species habitat by alien woody plants. In addition, intensive cattle production and agriculture also constitute relevant threats to the species.Centro de Estudios Parasitológicos y de VectoresUniversity Of HelsinskiFinnish Museum of Natural Histor

Descubrimiento de una población aislada de la tarántula enana homoeomma uruguayense (Araneae, Theraphosidae) en el centro de Argentina

El género Homoeomma presenta trece especies que se distribuyen en Argentina, Brasil, Colombia, Perú y Uruguay. En Argentina, se citan dos especies, Homoeomma elegans en la provincia de Misiones y H. uruguayense en las provincias de Buenos Aires, Entre Ríos y Santa Fe. El objetivo de este trabajo es reportar el primer registro de Homoeomma uruguayense para las sierras centrales de Argentina, lo cual corresponde al registro más occidental del género en este país. Además, se proveen datos sobre la historia natural de la especie, algunas notas sobre el comportamiento sexual y mediante el modelado de distribución de especies se discute sobre la distribución geográfica de la especie y los factores que pudieron conducir a este patrónThe genus Homoeomma has 13 species distributed in Argentina, Brazil, Colombia, Peru and Uruguay. In Argentina, two species are cited, Homoeomma elegans (Gerschman & Schiapelli, 1958) in Misiones province and H. uruguayense (Mello-Leitão, 1946) in Buenos Aires, Entre Ríos and Santa Fe provinces. The objective of this work is to provide the first record of Homoeomma uruguayensis in the mountainous system of central Argentina, belonging to western record of the genus in this country. In addition, we provide data on natural history of the species, some notes on its sexual behavior and through the species distribution modelling we discussed about the geographic distribution of the species and factors that could led to this pattern.Fil: Ferretti, Nelson Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Copperi, Maria Sofia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Pompozzi, Gabriel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; Argentin

Preys and capture sites used by crab spiders (Araneae: Thomisidae and Philodromidae) in a grassland of central Argentina.

La distribución de los depredadores y flores son factores importantes que influyen sobre la elección del sitio de forrajeo por los visitantes florales. Los depredadores como las arañas cangrejo pueden determinar la estructura de las comunidades de visitantes florales y afectar la polinización de las plantas. Los objetivos de este trabajo fueron (a) evaluar el uso por las arañas cangrejo de flores o inflorescencias (en adelante unidades de atracción floral, UAF) como sitios de captura; (b) determinar características que pueden afectar el uso de los sitios de captura; y (c) evaluar la relación entre el tamaño de las arañas y el de sus presas. Recorrimos dos parcelas de una hectárea en el centro de la región Pampeana (Buenos Aires, Argentina) registrando todas las plantas entomófilas en flor y sus visitantes florales. Además, capturamos todas las arañas cangrejo con y sin presa registrando las UAF que utilizaron como sitio de captura. Medimos y evaluamos la relación entre el tamaño de las arañas y de sus presas. Las arañas cangrejo utilizaron como sitios de captura las UAF más abundantes y con mayor riqueza de visitantes florales, independientemente de si eran flores o inflorescencias. Por otro lado, el tamaño de la araña podría determinar el tamaño de su presa. Encontramos una asociación positiva entre ambas variables, aunque este resultado fue variable dependiendo de los órdenes taxonómicos de las presas. Estos resultados sugieren que las arañas cangrejo pueden tener un papel relevante modelando la estructura de las interacciones planta-polinizadores.Distribution of predators and flowers influence on the selection of forage site of flower visitors. Predators, as crab spiders, can determine the structure of communities of flower visitors and influence on plant pollination. The objectives of this study were: (a) to evaluate the use of flowers or inflorescences (hereinafter units floral attraction, UFA) by crab spiders as capture sites; (B) to identify traits that may affect the use of capture sites; and (c) to assess the relationship between the size of the spiders and their prey. We surveyed two plots of one hectare in center of Pampas region (Buenos Aires, Argentina) recording all entomophilous flowering plants and their floral visitors. In addition, we captured all crab spiders with and without preys, recording the UFA they used as capture site. We estimate and evaluate the relationship between the size of the spiders and their prey. Crab spiders used as capture sites the most abundant UFA and with higher richness of floral visitors, regardless of whether they were flowers or inflorescences. On the other hand, the size of the spider could be determining the size of the preys. We found a positive association between the two variables, although this result was variable depending on the taxonomic orders of preys. Those results suggest that crab spiders can have a relevant role as modelers of the structure of plant - pollinator interaction.Fil: Marrero, Hugo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Investigaciones de Las Zonas Aridas. Provincia de Mendoza. Instituto Argentino de Investigaciones de Las Zonas Aridas. Universidad Nacional de Cuyo. Instituto Argentino de Investigaciones de Las Zonas Aridas; ArgentinaFil: Pompozzi, Gabriel Alejandro. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Laboratorio de Zoología de Invertebrados Ii; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Torretta, Juan Pablo. Universidad de Buenos Aires. Facultad de Agronomia. Cátedra de Botanica General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Effects of different frequencies of fire on an epigeal spider community in southern Caldenal, Argentina

Fire contributes to the selection and distribution of plant and animal species, and for a long time, its effects were considered to be negative. But recently, its role has been reinterpreted from a conservation standpoint. Fire, together with other environmental factors such as temperature and rainfall, affects the diversity and abundance of arthropods. Spiders comprise a group of potential ecological indicators, because they are diverse, abundant, and easy to sample, and they interact with their environment, potentially reflecting any ecological changes. Our goal was to assess the effects of controlled fires of different frequencies on the abundance, diversity, and composition of a community of epigeal spiders in southern Caldenal, La Pampa, Argentina. We obtained samples in May, Nov., and Dec. 2006 and Apr. 2007 in an area of approximately 12 ha. We conducted controlled burns every 3-4 and 6-7 yr since 1991, and used pitfall traps to collect specimens. Adults (554 spiders) were collected, and 56 species/morphospecies were recorded. Leprolochus birabeni Mello-Leitao 1942 (Zodariidae) was clearly the dominant species (19.9% of the total). We found significant differences in the abundances and species richness values between sampling months. However, we found no significant differences in the Shannon-Wiener (H´) diversity index between burned and unburned areas. The species compositions were similar in burned and unburned areas.Fil: Pompozzi, Gabriel Alejandro. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Tizón, Francisco Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Pelaez, Daniel Valerio. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentin

The species of Grammostola (Araneae: Theraphosidae) from Central Argentina: taxonomy, distribution, and surface ultrastructure of coxal setae

Three species of Grammostola (Araneae, Mygalomorphae, Theraphosidae) from central Argentina are redescribed and illustrated. Moreover, their geographic distribution is reported. A new synonymy between G. vachoni Schiapelli and Gerschman 1961 and G. schulzei (Schmidt 1994) n. syn. is proposed. We did not find zones of co-occurrence with the three species but, in several localities, we found two Grammostola species in sympatry. The surface ultrastructure of three types of coxal setae was studied by scanning electron microscopy (SEM). Two morphological types of spiniform setae were found on the coxae. The first type consisted of short and strong piriform setae, with the surface completely covered by ridges, and the second type consisted of long and thinner spiniform setae, with a piriform basal portion. The basal portion of the setae had ridges, the central portion was smooth and the apical zone had numerous short barbs with curved tips. The different types of setae found in these Grammostola species are clearly distinguished, and could be new useful character to diagnose at least these species. In combination with other characteristics, these characters could probably help to solve the problems in other species of this difficult genus if not also other genera.Fil: Ferretti, Nelson Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Pompozzi, Gabriel Alejandro. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pérez Miles, Fernando. Universidad de la República. Facultad de Ciencias; Urugua