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

<p>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 <i>Acoptolabrus</i> ground beetles (Coleoptera, Carabidae, genus <em>Carabus</em>) in the Far East. <i>Acoptolabrus</i> 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 <em>Acoptolabrus</em> species.</p>