SPIDER COMMUNITIES OF NATURAL GRASSLANDS CHANGE ACROSS DIFFERENT ECOREGIONS OF URUGUAY

POMPOZZI, GABRIEL; DE SANTIAGO, MARÍA FERNANDA; BLUMETTO, OSCAR; SIMÓ, MIGUEL

Congreso; 22nd International of Arachnology; 2023

Grasslands are among the biggest and most bio-diverse ecosystems in the world and arecritically endangered by the expansion of agricultural lands and urbanization. In Uruguay,grasslands from different ecoregions are suffering different rates of fragmentation and loss.Therefore, it is important to enhance the basic knowledge of grassland biodiversity. Spiders area good model for ecological studies, and are good indicators of environmental change. Here,we evaluated if spider communities from natural grasslands are similar in different geographicsites of Uruguay. We worked in six different sites across the country belonging to threedifferent ecoregions: Basaltic Slope (BS), Gondwanic Sediment Basin (GSB), and CrystallineShield (CS). We sampled spiders with two methods (G-vac and pit-fall traps) seasonally duringone year. Overall, we collected 10498 spiders (2189 adults) belonging to 28 families and 99species. In general, the number of spiders collected in each site was similar, with the exceptionof CS, where we found the higher abundance, species richness and diversity. In addition, wefound significant differences in species composition between CS and the rest of the ecoregions.These results showed that similar natural grasslands in different ecoregions support distinctspider communities. Furthermore, Cristallyne Shield is one of the ecoregion with higher levelsof habitat loss which highlight the importance of conserve these ecosystems in diversegeographic locations to preserve the biodiversity of Uruguay.