Identification by Pupal Weight Using Cochliomyia macellaria and Chrysomya rufifacies (Diptera: Calliphoridae)


  • Emily Faith Knight Texas A&M University-College Station


In the case of homicides, forensic entomologists are very useful for pinpointing the post mortem interval. In order to accurately do this, they must possess a thorough knowledge of the morphology of blow flies as well as blow fly development. This experiment studies the difference in pupal weight amongst and across the two species of Cochliomyia macellaria and Chrysomya rufifacies in order to have a comparison. Maggots were collected from carrion and allowed to pupate. Once the pupae emerged, their weights were documented. The blow flies were sexed once they had reached adulthood. It was found that both male and female Chrysomya rufifacies weigh more in the pupal stage than do their Cochliomyia macellaria counterparts and are larger in size. By using pupal weight to more quickly identify the species, forensic entomologists will ultimately be able to estimate a PMI in a more timely manner.


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