Linking Environmental Gradients, Functional Traits, and Phylogenetic Structure in Meloidae (Coleoptera) Assemblages of Inner Western Anatolia

ABSTRACT Aim Blister beetles (Coleoptera: Meloidae) exhibit complex life cycles, strong host dependencies, and unusual dispersal strategies, yet community‐level ecological analyses remain rare. We aimed to identify the environmental drivers of Meloidae assemblage structure and species richness, assess whether species responses are taxonomically structured, and evaluate the extent to which functional traits mediate species–environment relationships. Location Inner Western Anatolia, Türkiye. Methods We applied a Hierarchical Modelling of Species Communities (HMSC) framework to 28 Meloidae species sampled across 487 sites. The model integrated environmental predictors, spatial and temporal random effects, taxonomic relatedness, and functional traits related to dispersal (triungulin phoresy, host type) and hind wing morphology derived from geometric morphometrics. Results Species exhibited pronounced and heterogeneous responses to environmental gradients, with clear taxonomic structuring at genus and tribe levels. Climatic variability—particularly precipitation dynamics during the activity period—emerged as a key driver of species occurrences, while topographic context further modulated responses through linear and non‐linear effects. In contrast, assemblage‐level species richness showed weak and context‐dependent relationships with environmental gradients, reflecting compensatory, taxonomically structured species turnover rather than uniform richness change. Functional traits played a limited and selective role: triungulin phoresy and variation in wing centroid size were associated with a small subset of environmental gradients, whereas most trait–environment interactions were weak. Residual co‐occurrence patterns were dominated by spatial structure, indicating that assemblage organisation primarily reflects spatial context and dispersal processes rather than stable biotic interactions. Main Conclusions Meloidae assemblages in Inner Western Anatolia are structured by heterogeneous, taxonomically patterned species responses to environmental variability rather than by simple richness gradients or universal trait effects. Integrating environmental, taxonomic, and trait information within a joint modelling framework reveals how compositional turnover, spatial context, and life‐history complexity shape insect assemblages in biogeographic transition zones under increasing anthropogenic and climatic pressure.