Phylogeographic analysis of character displacement in feeding phenotypes of snail-feeding Acoptolabrus ground beetles: Morphological measurements

Ecological character displacement predicts that interspecific resource competition results in greater trait divergence between species in sympatry than in allopatry. In this study, we characterize character displacement in 8 species of snail-feeding Acoptolabrus ground beetles (Coleoptera, Carabidae, genus Carabus) in the Far East. Acoptolabrus exhibit divergent feeding phenotypes, including species with a slender forebody for intruding large shells and species with stout heads and mandibles for crushing small shells. Distance measurements (in mm) deposited here are for evaluating body shape variation among 8 Acoptolabrus species.