The Limari River valley has considerable value in terms of agricultural production within the Norte Chico. The expansion of crop monocultures in recents years has increased biological vulnerabilities, such as the number of economically important arthropods that are considered pests and zoonotic agents. Based on the review of historical data, collections, literature and entomological prospections, we examined the spatial distribution of economically important arthropods in the Limari basin. A total of 5,418 arthropods (arachnids and insects) records were registered, most of them insects, particularly homopterans and coleopterans. The richness and spatial records were concentrated between Ovalle and the Punitaqui estuary, which are areas with higher agricultural activity. We hope these data may serve as a basis to understand the richness structure of pest species in highly modified agricultural areas.