Larval diet breadth and wingspan mediate landscape–richness relationship in butterfly communities

This dataset comprises butterfly community and environmental data collected from 50 semi-natural grassland sites in Serbia. It includes butterfly species occurrence and abundance, species-level functional traits (wingspan and host-plant specificity), and site-level community-weighted means (CWMs) for these traits. Landscape variables encompass both habitat composition (% cover of forest, grassland, and complex agricultural cover within a 2 km radius) and habitat configuration (edge density, mean size of the nearest natural patch, and distance to the nearest natural patch). Accompanying R code is provided for all analyses, including trait distributions across the butterfly dataset, and generalized additive models (GAMs) examining the effects of landscape variables and their interactions with functional traits on butterfly species richness.