Wing morphometrics for identification of forensically important blowflies (Diptera: Calliphoridae) in Iberian Peninsula

Abstract

Calliphoridae is a family of Diptera of great forensic interest because some of its species belong to the sarcosaprophagous diptera community, as their larvae are necrophagous or necrophilous. In the Iberian Peninsula there are six species that stand out, as they are the first insects to arrive at carrion: Calliphora vicina, Calliphora vomitoria, Lucilia sericata, Lucilia caesar, Chrysomya albiceps and Chrysomya megacephala. To differentiate among these blowflies, we compared the value of using traditional and geometric morphometrics by performing a morphometric analysis of the wings (shape and size). A total of 600 individuals were considered, segregated by species and sex equally. Seventeen landmarks per wing were recognized, and then centroid size and shape analyses were performed using geometric morphometrics, and size using traditional morphometrics, to identify species and sex. The results showed differences in shape among the species and it was found that landmarks 2 to 11 were the most variable, while the landmarks located at the base of the wings were relatively stable. However, according to both traditional and geometric morphometrics, no significant differences were found among species in wing size (Calliphora vicina, Chrysomya megacephala and Lucilia caesar were indistinguishable), but females were larger than males (except for the two Chrysomya species). Our results indicate that the use of geometric morphometrics to analyze wing configuration (shape) is an easy-to-use tool that helps to distinguish among common blowfly species of forensic importance.