Surface activity, sex ratio and diversity of scorpions in two different habitats in an Arid Chaco reserve, Argentina

Abstract

Scorpions are one of the most important taxa of predators in terms of density, biomass, and diversity in various areas of the world. In this study, we compared population- and community-level data between a mature and a secondary forest in the Chancaní Reserve (Córdoba, Argentina). Scorpions were collected using pitfall traps (54 nights per site), and their nocturnal activity was observed by means of UV light (26 nights per site) over 7 months. Seven species of scorpions (1964 individuals) were observed in the study area (Bothriuridae and Buthidae). Brachistosternus ferrugineus composed >74 % of all individuals and was numerically dominant in most months. It was the most common species sampled with UV light method in all months (85.73 % in mature and 81.80 % in secondary forest). Timogenes elegans was the most common species sampled with the pitfall traps method in secondary forest (48.58 %). General sex ratio (males:females) for B. ferrugineus was 1:1.24 and for T. elegans was 1:0.53. The Shannon index was not significantly different between sites. Species richness was similar, and the Jaccard index was Cs = 0.86, indicating that both sites share 86 % of the species. Tityus confluens was the only species not shared between sites. Our results indicate that species composition in regenerating forest resembles that of primary forest after c. 15 years, but the relative abundances of these species differ.