Data from: Utility of geometric morphometrics for inferring feeding habit from mouthpart morphology in insects: tests with larval Carabidae

Feeding habits are important life-history traits in animals; however, methods for determination are not well established in many species. The larvae of the beetle family Carabidae are an example. This study tested the utility of geometric morphometrics of mouthpart morphology to infer feeding habits of carabid larvae. Using Pterostichus thunbergi as a model system, larval feeding habits were inferred using geometric morphometrics of mouthparts and the results were compared with those from rearing experiments. Rearing experiments indicated that P. thunbergi larvae are carnivores that require snails as an essential part of the diet. Through geometric morphometrics, associations between mouthpart morphology and larval feeding habits were confirmed for species in which these two traits are known. A discriminant analysis using these associations classified P. thunbergi larvae as snail/slug feeders—a result compatible with the rearing experiments. Geometric morphometrics also revealed that morphological integration and ontogenetic shape change might play roles in the diversification of mouthpart morphology. Overall, these results show the utility of the geometric morphometrics of mouthparts to infer feeding habit and to elucidate mechanisms of mouthpart morphological diversification in the study group, and serve as a basis for future studies of other insect groups.