Intensive agriculture has led to a significant global decline of biodiversity. However, agroecosystems like olive groves can serve as biodiversity refuges, especially in arid environments, by acting as resource islands that promote the persistence of multiple species, including arthropods. The structural complexity and productivity of olive groves typically increase with age, enhancing their ability to sustain high biodiversity. In this study, we examined how epigeal arthropod diversity patterns vary across olive orchards of different ages in the Huasco Valley of Chile’s Atacama Desert. We hypothesized that older olive orchards, with greater structural complexity and productivity, would harbor higher arthropod abundance, diversity, and distinct community compositions than a younger olive orchard. To test this hypothesis, we sampled epigeal arthropods in three olive orchards of different ages (young, intermediate, and centennial) using pitfall traps and characterized each orchard’s structure and productivity (NDVI). Our findings indicate that olive orchard age is related to arthropod composition and abundance but not diversity. Young and intermediate olive orchards had higher arthropod abundance, dominated by isopods and hymenopterans, while entomophthorans and mites predominated in the centennial orchard. Each orchard harbored a unique arthropod community, with NDVI being a key factor in the centennial orchard, dry weed biomass in intermediate orchards, and leaf litter in young groves. These results suggest that the structural characteristics associated with olive orchard age play a crucial role in shaping arthropod communities in arid environments, highlighting the importance of habitat management within groecosystems for promoting biodiversity.

In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the fauna—particularly insects—associated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.

The genus Elasmoderus is a group of the orthopteran family Tristiridae distributed across the transitional region of South America, Andean areas of Peru, Argentina, and Chile, the low-altitude desert and semidesert territories of Chile, and the steppe areas of the Argentinian and Chilean Patagonia. This genus is endemic to the extreme arid environments of north-central Chile and is famous for its adaptations to such habitats. Based on original and published data, we characterize the geographical distribution and discuss the history and ecology of this genus. Within this genus, Elasmoderus lutescens is the most widely distributed species, mainly in coastal and interior environments, followed by E. minutus, a small-sized species with a more restricted distribution range that is currently categorized as Vulnerable in Chile. Another relevant species is Elasmoderus wagenknechti, which is concentrated in coastal and interior environments of the Coquimbo region, where it can be very abundant. This species is economically significant and can damage crops and natural vegetation. Our findings highlight the importance of researching native insects to understand the role they play in semiarid ecosystems and to develop a basis for conducting long-term studies in
northern Chile.