Studies on Larval Dispersal in Two Species of Blow Flies (Diptera: Calliphoridae)

Abstract

The blow fl y larvae leave the food source after reaching maturity, and begin to disperse in order to fi nd suitable places for pupariation, a process commonly called postfeeding larval dispersal. Some important aspects of this process were studied by allowing the postfeeding larvae of Chrysomya megacephala (Fabricius) and Chrysomya rufi facies (Macquart) to disperse from the center of a circular arena. The arena was divided into 4 circles starting from the center in order to determine the location of each pupa. The relationship between distance from the center and the weight of each pupa was evaluated statistically. It was observed that the lighter larvae tend to move longer distances. The greatest concentration of pupae was found in distances lesser than 100 cm in both the species though it was more evident in case of C. rufi facies. The study of this dispersal process can be important while estimating the minimum postmortem interval (PMI) of human cadavers during forensic investigations.