Composition and life cycles of necrophagous flies infesting wrapped and unwrapped rabbit carcasses in Johor for forensic applications

Abstract

In forensic cases, corpses are frequently discovered wrapped in some material, probably as a means for disguising, as well as enabling easier handling and preventing evidence transfer. The use of such wrapping materials may affect insect colonization patterns, which in turn causing erroneous estimation of post-mortem interval (PMI). Hence, this present study utilized rabbit carcasses wrapped in a used rug with both sides remained open provided empirical data on species composition and completion of life cycles of necrophagous flies infesting in Johor, Malaysia. Result does not revealed differences in species composition between the wrapped and unwrapped rabbit carcasses. Six necrophagous fly species (viz. Chrysomya megacephala, Chrysomya rufifacies, Hemipyrellia tagaliana, Ophyra chalcogaster, Ophyra spinigera and unidentified Sarcophagidae) were consistently observed in all the decomposing wrapped and unwrapped rabbit carcasses during the three replicate experiments. While completion of life cycle for Sarcophagidae was not observed during the 30 days period of observation, completion of life cycles for the remaining five species i.e. C. megacephala (7.66-7.91 days), C. rufifacies (8.33-8.50 days), H. tagaliana (~14 days), O. chalcogaster (~15 days) and O. spinigera (~16 days) were observably similar in all the carcasses examined in this present study. Since forensic entomological baseline data for Johor on oviposition and completion of life cycle for these necrophagous flies remain unreported, the results reported here may prove useful for estimating minimum PMI via entomological assessment within this region or within the similar biogeoclimatic conditions.