Population analysis of Forensically Important Calliphoridae on Pig Corpses in Taiwan

Calliphoridae flies (blow flies) are the most useful insects for the investigation of victims' death date. In order to understand the distribution of active species of blow flies in Taiwan, we collected forensically important blow fly samples from pig carrions during 2002 to 2006 in Northern and Southern Taiwan in different seasons. In this work, we proposed a simple key modified from that of Wallman and Chang used for identifying forensic blow flies. Our results showed that the population of Chrysomya megacephala and Chrysomya rufifacies are the two most dominant flies in Taiwan. Among the two species, Chrysomya megacephala is more active than Chrysomya rufifacies in Northern Taiwan. However, Chrysomya rufifacies has dominance over Chrysomya megacephala in Southern area. During the cool seasons, Chrysomya pinguis is the prevailing species over the Chrysomya megacephala and Chrysomya rufifacies , suggesting that Chrysomya pinguis is an important blow fly for estimating PMI in the cool seasons. Lucilla and Hemipyrellia were much fewer than Chrysomya for a year round in Taiwan. And further, Lucilia porphyrina were only observed in Northern Taiwan in winter. These data would be beneficial for the PMI application in Taiwan.