<p>Agricultural expansion transforms the structure of tropical landscapes, altering the environmental filters that determine the functional composition of insect communities. We evaluated the variation in the functional composition of phytophagous scarab beetles (Coleoptera: Scarabaeidae) in response to landscape composition metrics (percentage of area) and configuration metrics (patch shape and inter-patch distance), together with local variables (canopy cover and elevation), in the Serranía del Perijá, northern Colombia. Four landscape windows, defined as rectangular sampling units of approximately 4 km² and separated from each other by at least 1.5&#xa0;km, were surveyed, each including three land-cover types (forest, regeneration, and crop). Six functional traits related to dispersal and resource use were measured. Functional composition was analyzed using community-weighted means (CWM), principal component analysis, and generalized additive mixed models. A total of 3661 individuals representing 30 species were recorded. At the regional scale, no significant differences among cover types were detected; however, trait–environment associations emerged within landscape windows and differed among traits and cover types. Dispersal-related traits showed detectable but context-dependent responses to spatial gradients, particularly in regeneration areas, whereas biomass and diet exhibited weak or inconsistent patterns. Overall, these results indicate that functional trait responses are heterogeneous and depend on environmental context rather than a single dominant landscape gradient, underscoring the importance of integrating landscape heterogeneity and local conditions into restoration and agroforestry management strategies aimed at maintaining functional diversity in fragmented tropical landscapes.</p>