Araneofauna (Arachnida; Araneae) do Parque Estadual do Turvo, Rio Grande do Sul, Brasil

Abstract

The araneofauna of the Neotropical region can be considered undersurveyed and lacking standardized inventories that can be used as a base for biodiversity studies. Spiders are recognized as important components of forest ecosystems and appear to be good organisms for studies concerning biodiversity standards. A survey was carried out in the Parque Estadual do Turvo, Rio Grande do Sul, Brazil to determine the richness and composition of the spider fauna. The Park is a protection area that includes the only remainder of the Floresta do Alto Uruguai in Brazil. Four expeditions were conducted over the period of two years, in Spring and Autumn (2003-2005). The main sampling technique was the beating tray, sampling the vegetation along the trails inside the park. Additionally, pitfall-traps, Winckler extractors, nocturnal manual collecting and random samplings were used. Shannon-Wiener (H') diversity indices and rarefaction curves were calculated for the beating tray samplings. A total of 8724 spiders belonging to 37 families were collected. Of these, 34% (2946) were adults, distributed in 31 families, 157 genera and 447 morphospecies. The richest families were Salticidae (23%) followed by Araneidae (18%), Theridiidae (16%) and Thomisidae (9%). In the beating tray samples 29 families were recorded. The most abundant families (including young individuals) were Salticidae (23%), Araneidae (18%), Thomisidae (14%), Theridiidae (12%) and Anyphaenidae (12%). Nineteen species presented a percentage higher than 1% of the total of collected adult individuals. The most abundant being Thwaitesia affinis O. P.-Cambridge, 1881 (Theridiidae), Tariona sp.1 (Salticidae) and Misumenops argenteus (Mello-Leitão, 1929) (Thomisidae). The Spring periods revealed more adult individuals and species and the Shannon-Wiener (H') diversity was considered higher in the periods of Autumn. The rarefaction curves did not reach asymptote, suggesting the existence of non-sampled species. The spider richness registered in this survey is the greatest observed for Rio Grande do Sul, and the second greatest for Brazil. These information show the importance of this ecosystem for biodiversity conservation in Brazil.Keywords: spiders, inventory, Neotropical, biodiversity. A região Neotropical é considerada pouco amostrada com relação à sua araneofauna, carecendo de inventários padronizados que possam servir de base para estudos de biodiversidade. As aranhas são consideradas como importantes componentes dos ecossistemas florestais e aparentam ser organismos ideais para estudos de padrões de biodiversidade. Neste estudo foi efetuado um levantamento da riqueza e composição da fauna de aranhas do Parque Estadual do Turvo, Rio Grande do Sul, Brasil, local que protege o único remanescente representativo da Floresta do Alto Uruguai no Brasil. Foram realizadas quatro expedições semestrais, durante dois anos, no outono e na primavera (2003)(2004)(2005). Como principal técnica de coleta foi empregado o guarda-chuva entomológico, com o qual amostou-se a vegetação arbór...

Diversity, composition and phenology of araneid orb-weavers (Araneae, Araneidae) associated with riparian forests in southern Brazil

“…other inventories as well (podgaiski et al, 2007;BaldisseRa et al, 2008), being known from grass and scrub vegetation (levi, 1995). This holds true here as well, since most (45%) of these spiders were found in the grassland edge.…”

“…11), being represented mostly in the forest interior (66%), but not recorded in Sinos riparian forests. It has been sampled from restinga shurbland and seasonal deciduous forest in RS State (RodRigues, 2005;podgaiski et al, 2007). Micratena guanabara was recorded from all rivers also with a preference for forest interior (92%); it was not recorded for either autumn or winter (Fig.…”

“…Spiders in this family are generally among the most abundant and speciose of those sampled from the treeshrub plant strata in faunal inventories in southern Brazil, even from distinct ecosystems (indRusiak & kotzian, 1998;BaldisseRa et al, 2004;RodRigues, 2005;silva & aRaujo, 2005;Bonaldo et al, 2007;podgaiski et al, 2007;BaldisseRa et al, 2008;RodRigues et al, 2014). A species list was presented by indRusiak & Buss (2003) for the central region of Rio Grande do Sul State, and in the list of spiders species of Rio Grande do Sul State (Buckup et al, 2010) cite Araneidae as the family with the highest number of species to the State (210 species).…”

“…17), and mostly in the forest interior (77%). Araneus omnicolor according to levi (1991) is to be found in humid forests; it has been recorded in various studies from different ecosystems in RS State (indRusiak & Buss, 2003;RodRigues, 2005;silva & aRaújo, 2005;podgaiski et al, 2007).…”

Activity of Juvenile Tarantulas in and Around the Maternal Burrow

“…There have been many spider community studies in the neotropics Dias et al 2005;Indicatti et al 2005;Raizer et al 2005;Sandoval 2005;Pinkus-Rendón et al 2006;Podgaiski et al 2007). As a typical megadiverse group, spiders have gained wide acceptance in ecological studies as indicators of environmental quality (Clausen 1986;Maelfait et al 1990;Churchill 1997).…”